What Home Depot insulation have you used under your carpet?

I'm laying down a layer of GTMAT first, then a layer of thermal reflective insulation which also has some some deadner sandwiched in there. Then on the underside of the car, that is ready to get a couple of coats of the Lizard Skin Ceramic sound deadner/thermal insulator...
Hoping for a nice cool ride and easy on the ears, until I hammer on it.