Heater core hose inner diameter?
 

Would anyone know the inner diameter of the heater core hose? I want to back-flush the heater core, as it is plugged, and I'd like to pick up something like this:

Attachment 244961

(without the filter). This would come in really handy, as it will allow me to join the hose coming out of the heater core with another long hose that I can run to a bucket to collect everything.