The Summerset Double Side Burner Insulating Grill Liner (GL-SB2) is a safety requirement when installing Summerset Double Side Burner (SB2) and Pro Double Side Burner (SB2PRO) in an outdoor kitchen island built with any combustible materials — lumber, OSB, resin composite, or similar framing. Building codes in most jurisdictions require an insulated liner when combustible frame construction is used. The liner is a double-walled stainless steel sleeve that fits exactly to the grill model, creating the required heat barrier between the grill and the island frame. #304 stainless steel. Gold Standard Lifetime Warranty.