[kressej]

I had no heater, but a Red Head gadget on the inside where one funnel shaped piece slides inside another, so you can have it closed, half open or anywhere in between. I opted for a novelty heater, sawed off 23" of trombone with the bell and attached it with stainless zipties. Finally got rid of the rattles... Now its a real eye catcher especially when someone looks in the hood louvers and says "What is THAT???". It works about as well as the others!