Double the sockets double the power LampBulb sold separately Compatible with StudioPRO 45W 65W 85W and 105W lamps Best PhotoVideo Use food peopleportraits plants jewelry crafts fashion interviews and more Center umbrella mount easily secures any standard umbrella light modifier This double socket is made of two sturdy polycarbonate housings and each socket independently tilts forward or backward for precise lighting package inlcuded Pack of 1 Double Bulb Holder with pack of 2pcs e27 base socket