3M Fire Barrier Cast-In Tub Box Assembly 3TB Foam 3 in 6/case

Creates a void on the top surface of a concrete slab for plumbing access. Fastens directly to a 2-inch (50.8 mm) 3M(TM) Fire Barrier Cast-In Device for Metallic Pipes. Remove 3-inch (76.2 mm) foam insert after slab is cured to create 3 in. (76.2 mm) deep void.