SELKIRK Sure-Temp Double Wall Adjustable Smoke Pipe DS-EZAJ-12 adjustable length. Installed at least 2 over a standard length, this part provides from 3-1/2 to 10 of adjustment. It can also be used as an alternate connection to the appliance. 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. Length Adjustable 12 to 18 , Inside Diameter 6 , Clearance To Combustibles 6 , Finish Matte Black, Material Stainless Steel Liner Galv Jacket, Pkg Qty 1