3M Fire Sealant System WL7169 Rectangular Duct Firestopping System
3M Fire Sealant System WL7169 Rectangular Duct Firestopping System Max 26 in. x 40 in. steel duct.U400 or V400 Series wall. Max opening 1617 sq. in. with max dimension 42 in. Concentric or eccentric installation. Min 1/2 in. to max 2 in. annular. 2 hour F. 0 hour T. Retaining angles required. Caulk only system.