4" Diameter x 2-3/4" Depth, Draft Tight, Ceiling Fixture Electrical Outlet Box, 26 CUIN, Angled Side Nails For Mounting, For Use With Non-Metallic Sheathed Cable, High Strength Black Polycarbonate Withstands Temperature Extremes, Meets Energy Efficiency Requirements For New Homes, Features A 1/2" Offset Flange To Ensure A Flush Fit In 1/2" Drywall, Foam Gaskets Over Cable Entry Points Provide Vapor Tight Seal Preventing Flow Of Air Through Box, UL Listed.