I second the Sprayway brand. I use it on the Lexan/Plexiglass R-Model rear window of the mustang and it does and excellent job on that and on the windshield. I have had good result with that and BLUE paper towels, the Scott Garage/Shop brand. They carry the Sprayway brand at Costo as well, comes in a 3 pack. It's a nice foam when it comes out. Sandy