K-FLEXUSA 6RSXG3X4068 Insulation Sheet,PSA Back,36x48x3/4 In

I used the sheet to insulate a motorhome holding tank, so I could use the motorhome in freezing weather without worrying about the water freezing in the tank and damaging it. The tank had a heater installed by the factory, but it was useless without the added insulation. The foam was easy to cut to size and apply. The only drawback is the rubbery foam is unprotected, and suffered some damage from rocks thrown by the rear wheel ahead of it. A longer mud flap stopped that. Water doesn't affect it, however.