Elco Lighting PSA33 Socket Adapter Med. Screw into GU10 with LampElco Lighting PSA33 PSA33 Product Description Elco Lighting Socket Adapter Med. Screw into GU10 with Lamp Features: Socket Adapters, Extender, Adapted Lamps and Sockets. About Elco Lighting: Founded in 1991 by its president, Steve Cohen, ELCO Lighting develops and markets lighting products for commercial and residential applications. Founded on the philosophy that high quality commercial and residential lighting should be sold at a fair market price,