A/C knob
 

The knob on my friends 2004 RX-8 broke and he's looking for a new one. It's the one that adjusts the temperature, the one on the passenger side.

Same thing happened to me. Had my dealer order it. It's covered under the warranty. It took my dealer three tries to get the correct knob.

its covered under a tsb by mazda

Yeah, I wouldn't be your man for knobs as our introduction explains.
Paul.