What Are Putty Pads & When Are They Required? | GRJ
IsoBacker | Acoustical Outlet Backer Putty Pad, Fire Rated - Kinetics Noise Control | Manufacturer
Amazon.com: 3M Fire Barrier Moldable Putty Pads MPP+ - Shapeable Firestop Pads for Wall Openings and Through Penetrations - 9 1/2" x 9 1/2", 20/case - Red : Office Products