Designed with double wall construction and a durable stainless steel inner liner. Intended to be used in place of standard single wall stove pipe. Interlocking joints, secured with screws provided, allow for quick and easy system assembly. Air space between inner and outer pipe allows reduced clearance to combustibles. 6" clearance to combustibles for 6" pipe as compared to 18" for standard single wall pipe. Engineered for superior smoke venting and safety. Helps reduce creosote build-up. Installation requires no cutting. Stainless steel inner liner, matte black steel outer casing. 6" I.D. Net assembled length is 1-1/2" less than listed lengths.