LOL... my "tire Norelco" was my 11 year old son who made the mistake of telling me he was bored one day. My tires are now stubble free. :D

Not to worry, I didn't take it that way either. Just wanted to word my response strongly enough that you'd realize I wasn't BSing you. ;)SWEET! Now you GOTTA get on this thread after you get them and let us know how right we all are! :D

Today is the first day of anything other than cold-dry weather that I've had a chance to drive them ... it's warm and rainy in Chicago today.

Wet traction - very good! Wet/salty traction (normally a very slippery combo) very good too!

Stew

For anyone who missed this, I finally got a chance to drive these tires on icy/snow packed roads. They are great on that too! Check 2 pages or so up for the review.

I plan to get some Pirelli PZero Nero M&S tires this week. I was wondering if anyone who has these already has noticed a change in mileage as a result of the wider tires compared to stock.

Just took a recent trip, (about 250 miles), and no difference as far as MPG. Forgot to take the GPS with me to verify the MPH difference. As soon as I do, I will post. :)

Just an update:

I've had several opportunities of late to drive my RX-8 on truly nasty roads with these Pirellis, and I have to say my initial impression still holds - these tires are great on slick roads. I suppose "true" winter tires would be better, but with these I have at least equal if not better traction in my '8 as I have driving my wife's Mazda 6S.

Omicron: You da' MAN
 

Want to second Omicron's opinion about the Pirelli's! I had my first try in inclement weather driving on icy roads from the recent freezing rains here in NJ. I was quite pleased with the tires in the icy stuff but I still have not had a chance to evaluate snow performance.

Also, just as Omicron had predicted, these tires have firmed up compared to the squishy feel when I first put them on (see original post below). After a few hundred miles, they do seem to have firmed up, although that could be due to the power of suggestion as well as a fading memory of the OEM feel. However, still no match for the razor response of the OEM Potenza's. I would chalk that up an added half inch of tire due to the 17 inch wheels.

I bought these tires on the recommendation of Omicron and others. I couldn't be happier. Dry performance is great, trading in a little turn-in for a little less harshness. Light winter weather seems fine so far. Overall, a good compromise for someone who wants to drive in light winter weather but does not have to drive in the heavy stuff and still wants great dry performance.

================================================== ====
below posted in November:

Pirelli PZero Nero M&S 235/45-17

--------------------------------------------------------------------------------

Bought a set of PZero Nero M&S for the winter season. I wanted to give a little review since I have had them on for a couple of weeks now.

I had TireRack mount these tires on new wheels - Kazera KZ-T. Not the best-looking wheel but the price was cheap and they had two desirable qualities: light weight and 48mm offset. Wheels are advertised to weight 19.4 pounds. I wanted an offset that closely matched the 50mm stock measurement so that feel of the setup would closely match stock. I was hoping for an 8in wide wheel but they are not that typical, particularly in the 17in diameter that I chose to keep the price down. This wheel is 7.5in wide and I had some concern about a 235mm tire width, but the 7.5in was in the acceptable range according to TR's spec page. Another reason I chose a 17in wheel is that there are precious few High Performance All-Season tires in an appropriate 18in diameter size. You can get a pretty good selection at 245/40-18, but that was wider than I wanted to go for a winter tire option.

I chose the Pirelli after see good reviews both here and on the TR site. Went with the 235/45 instead of the 245/40 again because I didn't a significantly wider tire than stock for winter use.

First impressions: Wheel is barely smaller in diameter as compared to stock, maybe 2/10ths of an inch. Speedo should be around 1% off, no sweat. I had anticipated this as the Pirelli seems to have the largest diameter of all the 235/45-17 tires listed on the TR rack site. From appearance perspective, hard to tell that the 7.5in wheel width was the bottom of the acceptable range. I have a hard time believing that this tire could be mounted on a wheel 2 inches wider, 7.5 looks like the perfect wheel width. Tire/wheel combo is noticeably lighter than stock, maybe three to four pounds lighter; I didn't get a scale out.

Driving impressions: Immediately noticeable that the car feels more "squishy" now. Best way to describe the feel is to imagine the wheels twisting within the tire in a side-to-side manner, not rotationally. I believe that is a result of the half-inch greater sidewall on the 17s. I also suspect that the sidewall is not as firm as the stock tire. I have gone to a higher pressure (38 PSI) but I can still feel the "squish". Something to look forward to when I put the summer Bridgestone's back on. Grip seems very good and cold days are not a problem now. One advantage is that these tires are not as harsh over road irregularities; I guess "squishy" does have an upside. Wet grip is very good, but I have not had a chance to drive in snow yet. Stay tuned.

A quick note on the Bridgestones: Rotate! I had not rotated my tires yet, 8,000 miles in 11 months. The rears were noticeably more worn than the fronts. Also, having driven an RX-8 through last year's winter on the Potenzas (albeit with another car at my disposal for wintry days) I will reiterate what everyone already knows - Potenzas cannot be used in the slightest of snow. They are also quite slippery in the cold - until warmed up. When it got down to the teens, I could feel the tires were so stiff that they were out of round, but a couple of miles would warm them up and dry grip would be no problem. Problem was that I picked up my RX-8 December 1st last year and by the time I realize that some other tire was required for the winter, there was not much selection left. I limped through the winter on the summer tires but vowed not to do that again. I had to force my self to leave the RX-8 at home on wintry days, and that is tough to do with any new car, particularly one as wonderful as the RX-8.

An update from me as well. I have about 700 miles on the new tires now. The mold release compound has worn off (along with most of the fuzzies), and on dry they stick like glue. I agree with Ti here ... slight reduction in turn-in crispness, but an increase in overall grip.

My other dry pavement note is that they seem to be much more progressive in terms of "at the limit" handling - you get more feedback as they are reaching their limit (but not squeal or noise - just a noticable sensation of being at the outer limit of traction) and they break free more progressively. I always had the sensation with the RE040s that when they would break free, they'd go straight from stick to slide with no warning and would spit me inot the weeds.

Snow handling: Well, if you follow the weather channel at all, you'll note that Chicago got HAMMERED this week with snow - about 14" in our area. Lucky me, I was out of town during most of it, and my RX-8 was safely ensconced in valet parking at O'Hare Airport. But, I got home Thursday afternoon, and while everything else was nicely plowed, my street had had only one pass on it when I got home - about 3" of loose, tracked up snow - I actually was excited about it. And they were terrific in it. No issues with the nose not knowing which way to go, the braking and starting traction were fine, and with the DSC/Traction control, it drove great. Definitely a terrific solution for wintry driving. I don't think I'd like to try to negotiate a mountain pass in 6" of fresh powder, but hey, that's not what I drive in around here.

Stew

The first snow in my 8. We got 6 inches today and my drive home on partially plowed streets and on my own non-plowed street was not quite as good as I expected with this car and these tires. On one section of partially plowed road, my 8 decided it wanted to drift with no prodding from me (I was in 3rd gear). I took it slow the rest of the way (slower than I would have gone in my Civic Si with RE910 all-seasons). When I got home, I could barely make up my driveway even after I shoveled all but 1/4 inch that was stuck to the concrete.

I'm a bit disappointed. The combination of RWD and these tires was worse than what I had with FWD and RE910s. Based upon comments here, I guess I expected more. I'll get another chance on the way to work tomorrow.

Some will say I should have gotten snow tires, but Cincinnati is not exactly in the snow belt, and I decided I didn't want them for the ten or less days each winter when snow is a problem. If it gets really bad, I'll drive my 4WD Tacoma.

I've been happy with mine in snow as deep as 3". Tonight's the litmus test. We're supposed to get a foot.

Do you have traction control on your RX-8? I find that that makes it simpler to drive in the winter, with less concern about oversteer. That said, I also have snow tires :)

Ordered a set from Tirerack
 

I just ordered a set of PZero Nero M&S 245/40WR18 to put on my stock rims from tirerack.com

Funny thing is I noticed that they had these listed twice on their site for the same $150 each. One listing said in stock, the other said special order so I called.

The sales rep., Alex I believe, said the in stock ones were the new model with an improved tread pattern; the special order was the old version.

I ordered 4 wheels of the in stock version.

Go figure!

Claude H.

Well I did it, and my results
 

So far.....not impressed at all.

That doesn't mean I've come across anything terrible, or that I think the tires are poor. I am literally just not impressed.

The ride with these new tires on was not drastically different as many people on this thread have claimed. The handling and cornering is virtually identical to OEM. Still...I wasn't to be daunted. After all, I got these tires as a performance alternative to swapping out snow tires.

We got 2 inches here in NoVA 2 days ago. I got through the flat areas of the metro area with minimal tire spinning. Hardly inspiring, but so far so good. Then I got into some traffic and on an incline.

I had to stop. You know what that means.

I OH SO GENTLY applied some gas and immediatley my tires broke loose. TCS light turned on and stayed on and my tires just spun and spun on that hill. The ass-end of my car drifted about 30 degrees off center to the right...and my poor RX8 just crawled up the hill a few inches at a time.

Not exactly the snow performance I was hoping for.

To be fair, as soon as I got going, a Jeep Cherokee 4x4 right behind me spun out on the same hill.

So, final thoughts...the conditions were bad. While the depth of the snow wasn't much (2 inches or so), it was packed down hard and formed an ice-slick type surface when combined with just enough snow to fill up your treads. Despite that, I was hoping for more. We'll see if it was just the hill and specific conditions, or if it basically sucks everywhere.

I did have the traction control and the DSC on.

i'm jealous i couldn't even get up a hill in m y8 on that day (and it had ben plowed)..I had to leave my car for a day until the snow melted enough i coul ddrive her. :( so i may of sucked for you that day but it was horrible for me and my crappy oem non-all season potenzas:p

Just great, I read all these glowing reviews of the PZero M+S and I order a set from Tire Rack after spinning out on Rt. 287 South in N.J. during a 1" snow storm last week on the stock RE040's. Now people are saying they're maybe not so great.

C'mon the PZero M+S have got to be better than the stocks in snow. Right???

Just a sidetrack, is anyone playing Burnout 3 on Xbox? The only thing that could make this game better would be running an RX-8 during a Road Rage race!! (Sorry, I'm not trying to hijack this thread)

I have the PZero M+S on my car. They are much better than the RE40's. Is there wheel spin, yes. Hell your driving on snow and ice for gods sake. Don't worry about the Pirelli's. You'll find you'll be able to go, stop and turn in snow. We just got 12" of the stuff in the last day.

Even though I had a bad experience with them, I know they have to better than the OEMs. I drove ultra high-performance tires in the snow one time about 5 years ago, and will never do that again. While I made it home with the Pirelli's with a little slipping, and traction was not as good as I expected based upon others' reports, I never would have been able to get very far with the OEMs. I also think that traction is not as good as it would have been in a FWD car with the same tires. I'm still refamiliarizing myself with RWD after 15 or so tears of FWD, and this may have been a factor in my feeling a bit uneasy with the PZero's.

Taka, stay away from the P zero rosso, I have had terrible luck with these tires as they came as standard equipment on my 03 Saab 9-3SS. Thye wear out at about 12000 miles in the center regardless of pressure. I ran them at the listed pressure and the center 3 bands are bald while the cornering bands still have a lot of life. Run them down a couple of pounds (thought the shape was rounding under increased temp/pressure at speed) and they continue to do the same.

Ok, we've got 2 people who have not written glowing reviews of these tires out of probably a couple of dozen (at least!) who have. Now because I kicked this whole thing off, I feel compelled to defend them. :mad:


These tires are NOT going to make you RX-8 drive like you've suddenly added 3000 Lbs and spiked tank treads to it. They're NOT going to make it into the ultimate winter driving vehicle, completely impervious to the roads regardless of how slick, icy, or snowpacked they are.

What they WILL do is give you dry road performance that is at least CLOSE to the OEM Bridgestones that come on the car, and ride somewhat nicer and quieter to boot. They will ALSO give you some measure of winter driveability that the OEM Bridgestones do not. Dedicated snow tires WILL be better than these tires if you live in a climate that requires them, assuming you're willing to (a) buy an extra set of wheels for the snow tires, (b) put up with the drawbacks of snow tires and (c) are willing to swap out your wheels twice a year. I wasn't.

And finally, please note that if all other things are equal, NO rear wheel drive sports car be as good as most front whel drive car on bad roads. FWD have most of their weight on the driving/steering wheels, while RWD cars like the RX-8 do not.

I appreciate the response, Omicron. I agree with all your points. There were a few people who had made remarks such as "I was cruising along, watching all these 4WD SUVs on the side of the road". These raised my expectations, probably above reasonable. The fact that 50% of the weight was over the rear wheels led me to believe that traction might be closer to FWD. My disappointment was therefore the result of high and possibly unreasonable expectations. In any event, I did get home, and I'm not going to trash the tires based upon one experience.

I trust that the people who pointed me in the direction of these tires knew what the tires could do (and the key here is in the next few words) relative to similar tires on an RX-8. I suspect that the PZero Nero M&S is above average for this category, and for that reason I am still glad I bought them.

Thanks Omicron and Fredw1 for your recent posts. You've helped clarify things for me and make me feel better about my PZero M+S purchase.

I know I'm not going to get snow tire performance with the M+S or even the equivalent perfomance to a FWD drive with similar tires. But, I just want to know that I'm not going to have that terrifying feeling that I could lose control at any moment even in minimally bad winter conditions like I have with the stock tires. And I think your posts confirm that.

Happy to help... sorry if I sounded grumpy. :)

Interesting ... it is unfortunate.

Thanks for the head up buddy.

I have had a set of the PZero Nero MS on my car for about 3 weeks now and am not all that impressed. They are quieter than the OEMs...and smoother, but I sometimes feel that their directional stability on dry roads is less than the OEMs. I get an odd feeling, almost like they have induced a bit of over steer into the car. There also is a grooved section of highway that I travel on and the PZeros are definitely more affected by the grooves than the OEMs were (with the OEMs I couldn't even tell I was on grooves).

The other day we had a small amount of snow fall on us that immediately turned to ice. Well, it was SCARY even going 2 MPH. Yes, I know that these tires won't help in icy conditions, but this was ridiculous. Going 2 miles per hour in stop and go traffic, combined with the car's front brake bias, low weight, at idle (auto), I was spinning my tires both slowing down and just coming off brake to move forward - the idle speed (600 RPM?) was spinning the tires! I got off the road and into a restaurant where I spent the next 3 hours going back and forth to the buffet until the roads and traffic cleared out.

Anyway, to make a long story short, I am not impressed with the performance of these tires so far. The over steer feeling is really weird...tread pattern?

And yes, they are the fuzziest tires I have EVER seen! I comment that I have wrapped porcupines around my rims...little rubber nubs everywhere! Good looking tires - but....

How was the other traffic dealing with the ice on the road? How were you comparing to FWD with all seasons, as well as all-wheel drives, etc?

It seemed that almost everyone else was doing much better than I was. Yes it was slick, but for me it was downright dangerous. I was skittering all over the place at 1-2 MPH. I am betting that if I had about 100LBS of sand in the trunk I would have done much better.

To answer your question, I didn't see anyone else slipping around like I was...fact is, I had this one 4 WD truck right on my...er...butt. So here I am spinning tires all over the place (brake off / brake on), fishtailing, etc., and he is right on me. Amazing! :mad:

The roads were awful...but I was surprised that the tires didn't seem to help as much as I had hoped. I hate to think what it would have been with the OEM tires.

Good Thing: The tires look AWESOME! I think I got 245/40x18 (if I remember correctly). Just a tad fatter....they look great.

Anyway, it shall be interesting to see how they do in a light snow...ice really isn't a fair test.

Now all I need do is go and buy a few sacks of sand...

Let me add that I did a few exit ramps at speed today (sand and salt mostly gone) and the tires seemed very good...better than the OEMs. A bit more responsive (slight over-steer?) also.

With those monster grooves, they should do well in the rain also. Splish splash!

I apologize to ask this question, I am sure it has been asked a million times, I nearly got into an accident in the snow last week. My baby is parked indoors now, and I am renting. Could someone please tell me what snow tires I can get. Thanks and sorry for asking this question.

Just spend some time in the forum where you found this thread reading other threads, or search on "Winter tires." You'll find LOTS of info.

Like I said...I was disappointed b/c I think I was overhyped by many people on this thread that these tires somehow do it all. I personally think they are just as good if not better than the stock tires for dry performance and better than OEM in the snow.

Bottom line is that's what I paid for.

Are they good snow tires? Hell no. Can you MOVE and TURN with them? Yes.

If that's good enough for you, then it's a great lower-cost investment than swapping out seasonaly. If you really need to drive in the snow more than occasionally, I'd strongly suggest going to winter tires. The 7.6 rating (or close, I can't recall) from Tire Rack is probably overstated.

With a 1 being summer performance tires and 10 being snow tires, I'd say these are about a 4, maybe a 5.

As others have said, there are lots of threads / opinions out there on this subject.

But one of the top-rated all-weather tires is what this thread is all about (PZero Nero M&S). The 245/40 - 18s will fit your stock rims and car with no problems. The roll-out is almost the same too so you won't have any problems with your speedo or traction control, etc.

One thing that you should realize is that the RX does not like snow or slippery conditions. It is a sports car. If you get any amount of the slippery on the road you really need to leave it parked nice and snuggy in the garage.

The rear-end is so light I am not sure tossing a couple of bags of sand in the trunk would help...tire studs or chains maybe...but not many communities like those items anymore. :(

Well, I respectfully disagree. On snowpacked roads with some ice, they have been fine. I get around as well as most of the SUVs and FWD cars are. No better, no worse. And Colorado gets some plenty cruddy roads. I have not tried them on pure ice though, nor will I if I can avoid it, because nothing short of metal studded snow tires work on pure ice.

Did I miss something? You state above that ".....at least CLOSE to the OEM Bridgestones..." I thought everyone said the PZeros were much, much better than the B'stones.

Well now... I guess I'll chime in on this one... Even though I've only had the PZeros on my 8 for about a month now, and have only driven a couple of hundred miles on them, I can say that they are definitely better than the Bridgestones. Although I haven't tried to "test" them out on snowy roads I have had the opportunity to try them on cold, wet road surfaces and these do perform better than the OEMs ever did. I was always nervous with the Potenzas, because they were really not "happy", (so to speak), on road surfaces that were cold. I won't even start in about the 1/4" of snow that I got stuck on, (with the OEMs), and threw a CEL. But as Omicron said, these are not snow tires - he (like me), got them so that in the event that if he was out somewheres and found himself in a situation with a sudden snow storm, he'd at least be able to get back home, and in his garage, (I think he mentioned that somewhere early on in this thread).
-Doccable

Omicron, I've been told, after making a somewhat similar observation to the instructors up at the Bridgestone/Toyota Winter Driving School up in Steamboat (www.winterdrive.com), that this may no longer be true with some of the newer winter tire compounds that are available. I spent last week in Seefeld Austria in an Audi Performance Winter Drive program using the new Audi 2.0 A4 AWD. Audi's school cars were equiped with Michelin "Invulda" studed snows (tread looks like what in the US market is being called the Ice-X.) The BWDS school vehicles (mostly 2005 Toyota 4Runners) have been out fitted with Blizzak Winter Duelers - no studs. The BWDS instructors (and they apparently do some of the tire testing for
Bridgestone) said that outside of a very narrow temperature range, and that being @ 32°F or 0°C or where ever your local highway departments particular chemical concoction has put the freezing point for the slush/water on the road, the new winter compounds are basically just as effective as studs as far a traction is concerned. Sounds implausibel, but that was their story, and they're sticking to it.

HTH someone.
mike

I get my M+S's installed on Tuesday, Feb 1 (and Tuesday can't come soon enough for me). Based on what I've read on this thread, I think it's just a matter of perception and what we expect from our replacement tires. For me, I just want to know that I have some level of control in even minimally poor winter conditions. I think the M+S will give me this control.

For me, I appreciate everyone's point of view on the tires. I know that I would have no idea what tires to choose if it weren't for this thread.

By the way, I'm bringing a copy of the Mazda TSB on how to deal with the TPMS when changing tires. I spoke with the installer and they were very receptive to my bringing the TSB - I was a bit worried they might get defensive, like I was telling them how to do their job.

I'll post back when I've had a chance to try out the tires in some less than ideal conditions.

Thanks to all!! :)

Yep... the bit about "on dry roads."

On slick roads, the Pirellis are FAR superior to the Bridgestones, which are like ice skates. :eek:

Well now that's certainly interesting, and it will be even more so to see if this proves true in the "real world." Good find! I also notice they were comparing an AWD sedan with studded tires versus a 4WD SUV though... and at the least there is a difference in vehicle weight. Might be marketing hype, might be true. Time will tell.

In the mean time, I'm happy with my PZeros. :D

Thanks for chiming in here, Doc. You'll have to let us know how it goes when you do wind up out in the next major storm.

Again, I just want to make clear I'm NOT suggesting that the PZeroes are poor tires. I never drove the OEM tires on snow, so I don't know how bad they are. I DO have experience driving Bridgestone Pole Position S02's on the snow, and can tell you it was a nightmare.

However, I thought that a 7.6 rating at Tire Rack would mean that they would do reasonably well. I figured this meant as long as I wasn't stupid with them (slamming on the brakes or trying to take off hard from a stop) I could drive normally in light snow or packed snow conditions. I don't expect to take a turn at 40 mph on the snow with them, but as it stands I slide quite easily with the PZeroes.

Some examples:

On a reasonably flat residential street with <1" of packed snow, if I apply the brakes moderately from 25 mph, I slide after about 10mph of deceleration.

On the same flat residental street with the same <1" of packed snow, if I accelerate moderately (30% of WOT, perhaps), I spin tires and move forward very slowly with the TCS light on.

On a moderate incline, starting from a stopped position on packed snow meant ZERO control with heavy rear-end sliding and the ass-end of the car drifting 30 degrees off center from the lane.

None of my driving thus far with the PZeroes has been on true ice...just packed (light to heavy) snow. The treads simply loaded up with packed snow and became smooth surfaces to spin against the packed snow on the road. Again, I'd put my confidence with normal driving on these tires in snowy conditions at about a 4 out of 10 or so. Better than summer tires, definitely, but not really super confidence inducing.

Happy Camper!
 

Got the M+S's installed Tuesday. So far so good. I can't tell much of difference between the stocks and these tires on dry pavement - that's a good thing for me. Waiting for the next bout of bad weather for the real test.

Interesting thing about the install -
I got the tires from Tire Rack and had them installed at the Front End Shop in Farmingdale, NJ. Front End Shop discovered during the install that one of the tires is out of spec on the roll-out. Not really sure what that means - but I do know that Tire Rack and the Front End shop are taking care of me very nicely.

Front End shop called Tire Rack and arranged to have a replacement tire sent out right away. For now I'm driving on the out of spec tire (no danger, they tell me) and when the new one comes all I do is go to Front End shop and they swap out the tire.

Very smooth, customer friendly resolution of a problem all taken care of directly between Tire Rack and Front End Shop.

I asked the Front End Shop how often they come across out of spec tires. They told me about 1 in every 15 tires is out of spec in some way. If that's anywhere near accurate, that's pretty dismal quality control by the tire companies. Scary.

Tire Rack and Front End shop - highly recommended!

My experience has been much the same. Not as good as I hoped, but better than OEM.

M+S in the Snow
 

Got my first experience driving on the M+S's in the snow this morning. Ocean County, NJ: 32 degrees out, snowing pretty hard, about 1" of snow on the non-highway roads.

Results: Much better than the stock RE040's. On the stocks, I couldn't even move on the same amount of snow. The M+S's got me going, gave reasonable traction (a little sliding - not bad) and felt much more stable than the stocks. Not snow tire like performance, of course, but not life-threatening like the stocks.

Exactly what I expected and I am very satisfied. :)

Very cool. :cool: This has been my experience with them too.

I'm sold. Recent mild weather in western Michigan has me itching to take my 8 out of hibernation, early. I contacted my dealer about costs to mount/balance the Pirelli's and found that they can't handle wheels with tire pressure sensors and are quite aware of how easy it is to break them. They suggested Discount or Belle Tire. I've had really good luck with Belle, so I checked with them first. They do a high volume in custom wheels, up to 24", and have no problems with pressure sensors. They just got some new Michelen machine that removes the tire without touching the rim - sounds pretty neat!

Price - Tire Rack currently shows $150 ea and shipping to Alto would be $36. I figured about $120+ for mounting. Belle's quote is $786, complete. Its $60 for the lifetime balance, rotate, flat repair, replacement policy. They admitted they would probably get them from Tire Rack and about 1-2 days from request to in-stock.

Unless the forecast changes, I'll probably be on the road next week!

Excellent - keep us posted! :D

Just got my 8 on 2/2/05, and because of the weather here haven't been able to drive her much. Am therefore considering the Pirellis. I know the question was asked earlier in this thread, but thought I'd ask if there are any new observations or updates: has anyone with the Pirellis noticed any effect on mileage? Thanks.

No change one way or t'other on mileage that I could detect.