Thomas & Betts 7020-8 Single Gang Box With Clamps Thomas & Betts 7020-8 Single Gang Box With Clamps Features: Single gang reinforced Phenolic box with high clamps, ears #8 snap-in bracket 150º C heat rated material Classified for two-hour firewall and fire-ceiling No knockouts 3-1/4" x 2-3/16" x 2-1/4"