1-piece, glazed porcelain lampholder. Features 4 screw terminals for continuous wiring and knockouts to fit a 3-1/4 inch or 4 inch outlet box. Twist-lock mounting provides quick and easy installation. 660-watt/250-volt. UL (Underwriter's Laboratories) and CSA (Canadian Standards Association) listed. 4-1/2 inch outside diameter. No. B01-49875-000: Color: White, Material: Porcelain, Bulb Type: Incandescent, Base Type: Medium, Wattage: 660W, Voltage: 250V, Number of Terminal Screws: 4 Terminal Screws, Fits: 3-1/4 In., 4 In., UL Listed: Yes, Pkg Qty: 1, Package Type: Box Thanks for shopping Hipp Hardware Plus's Online Store for all your DIY and Home Improvement needs. Remember Hipps Help!