Check the listing for details. 2pcs E27 Double Base Bulb Socket Adapter M10 Thread Lamp Holder 2 Light Socket. Color: Black, Condition: New. Listed at 15.75 USD. What is this?Suitable for all E27 screw bulbs, incandescent lamps, desk or floor lamps, ceiling lamps, home or office chandeliers, various DIY light fixtures, etc.What will I get?Color: BlackMaterial: Plastic, CopperHead: 2-light BaseMax Current: 4AVoltage: 250VACMax Power: 600WThread Size: M10*1Interior: Standard Medium E26/E27Light Head Size: 36 x 63mm/1.42" x 2.48"(Outer Dia*Heigth)Package Included: 2pcs x 2 Light Cluster Lamp Socket, 2 x Thread Fitting, 2 x Gasket, 2 x NutAre there any advantages of the product?Made of plastic shell and copper conductor, with good rust and heat resistance. That is good as a light fixture replacement in the office or home. How to use it?All lamp heads are connected in parallel circuits.