Metacaulk® Box Guard™ is a highly intumescent, fire-rated pad for use in | electrical boxes. When complying with the "24 I inch rule", it is inserted on the inside back wall of an electrical box. When exposed to fire, BoxGuard™ 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 UL411 wall assembly/section to ASTM E90. |