The 2164 Multifunctional Crab Clamp with 3.5" Ball Head Arm from SmallRig enables you to mount a 1/4"-20 threaded camera accessory, small light, or other component onto a rod or surface measuring up to 2" in width. The clamp arm includes a 180° mini ball head at each end, enabling you to position your accessory at almost any angle. The clamp tightens easily using its large wingnut and the 3.5" arm is fastened via a thumb-lever.