Sure-temp 6" x 48", 6T-48, All Fuel, Double Wall, Chimney Pipe Comes equipped with locking band and solid pack insulation Tested to withstand 2100 F and is UL listed Test helps to prevent product damage, or structural hazard during brief periods of this excessive chimney temperature Sure-temp 6" x 48", 6T-48, All Fuel, Double Wall, Chimney Pipe Comes equipped with locking band and solid pack insulation Tested to withstand 2100 F and is UL listed