Upgradelights Clamp on Uno Lamp Shade Holder (Downbridge Lamp Part). Shade fitter ring is approx 2 1/4 inches across with 3 screws to hold shade in place Downbridge Lamp Part Shade fitter ring Clamps onto the end of a standard lamp socket Downbridge Lamp Part Shade fitter ring Clamps onto the end of a standard lamp socket American family owned small business, USA based customer service. Always next day free shipping from NC.