The Stepp STPH Patch truck bodies have Triple wall construction, inner hopper constructed of 10 gauge material. Oil jacketed chamber to be constructed of 12 gauge material insulated with 2" of 1½# density hi-temperature fiberglass insulation. The heat risers are designed into the hopper to help evenly distribute heat into the center of material. Insulation cover to be 16 gauge. Mounted to the truck chassis with a spring loaded slip saddle mount.