6" DuraVent DuraBlack/DVL Stainless Steel Chimney Adaptor with Trim 6DVL-ADC This chimney adaptor with trim is used to connect from double-wall DVL and/or single-wall DuraBlack to DuraTech DuraPlus and DuraLiner for a through-the-wall or ceiling support installation. Required for proper connection. Approved for most fuel types 430-alloy stainless steel inner wall 2" clearance to combustibles ThermalTech blanket insulation eliminates hot spots Twist-lock connections for strong secure fits Able to vent large fireplaces and building heating appliances Clean smooth exterior finish 10â€-24†diameter pipes feature an .027†430 stainless steel inner wall and an outer wall of .029†galvalume or .027†430 stainless steel. A Refractory insulation is encased between walls. Only stainless pipes use the stainless end rings. Regular galvalume pipe uses galvalume end rings.