National Chimney 5" x 30' M-FLEX Aluminum Liner Kit for Gas Units

National Chimney manufactures our M-FLEX aluminum liner kits for appliances with A.F.U.E. of 83% or lower. Each aluminum kit comes professionally packed and includes: • UL Listed and Tested 2-ply aluminum liner • Aluminum mortar collar for slipping the liner through the thimble • Aluminum top plate with a 16”x 16” plate and a 2” high collar around the hole diameter • Aluminum cap, and installation instructions All M-FLEX aluminum liner kits come with a 25-Year Warranty and are listed to UL441.