Simplify the installation position of the arm and adjust any photographic lighting. Precise and the lock arm can be installed in any position to move when the knob is controlled or released. for head at the end of the 11 INCH arm makes you a comfortable use when you need any of the device. It can be adjusted at any and all movable joints can be tightened only by tightening knob. Supply 1/4 screw adapter suitable for cameras, lamp holders and other accessories.