Studio Slave Bulb Designed to work with all E27 screw light, accommodate light bulbs or slave flash, built in umbrella holder and light stand mount, easy mount to light stand and easily adjustable for different shooting angles. Perfect for holder your photo umbrellas, slave flash or light bulbs. It mounts on any standard light stand. The extra long cords help you move them freely to position it for best lighting effects. Easy to use screw in head will fit standard photo bulbs. This adapter/light holder will fit all your lighting needs from photo flood to strobe lights.