23.0 Cu. In. 4" dia. round fixture support box for use with nonmetallic sheathed cable - Machine tapped fixture holes - New work residential construction 2 HR fire resistive walls and ceilings (50 lbs. fixture support) - Polycarbonate - thermoplastic box - Size: Depth=2 15/16", Dia=4" - Mount with Nail-on with fetter ring nails