Metacaulk® Firestop for Electrical Outlet Boxes
Metacaulk® Box Guard™ is a highly intumescent, fire-rated pad for use in electrical boxes. When complying with the “24 inch rule”, it is inserted on the inside back wall of an electrical box.
When exposed to fire, Box Guard™ will expand forming a char that will seal off the opening and prevent the spread of flames and limit the temperature rise on the unexposed surfaces. A labor saving, economical alternative to putty pads. Great for retrofit jobs. STC 53 Rating, Tested in a UL 411 wall assembly/section to ASTM E90.
US Patent No. 6,207,085 & 6,252,167