COMBINATION PACK: This listing includes one 4'' square metal box and one 4'' toggle/decorator switch cover. Also includes a copper ground wire and screw. MATERIAL: Crafted from 1/16-inch pre-galvanized steel, the electric box and its cover are manufactured using premium quality material to ensure durability. Acceptable for use in 2-hour fire rated walls. SPECIFICATIONS: This electrical junction box has a capacity of 30.3 cubic inches. It is 4-inches square and has a depth of 2-1/8 inches. Trade size 2-gang. Also includes a raised ground provision. KNOCKOUTS: Designed for versatile usage, this electrical box has ten 1/2'' knockouts and six TKO knockouts. TKOs are extremely convenient and can be used either as a 1/2'' or as a 3/4'' knockout. (There are eight 1/2'' and four TKO side knockouts, and two 1/2'' and two TKO bottom knockouts.) BOX: This 4" outlet box is designed to use to enclose electrical wire connections, receptacles, or switches. Constructed using the welded method, this junction box is sturdy and strong. COVER: This 4" square exposed work cover includes the required hardware for mounting a toggle switch and a rocker switch. With its crushed corners, no bonding jumpers are required for this cover.