The joby action clamp locking arm provides a quick and easy way to mount your action camera to flat and round surfaces the locking arm with articulating ball joints allow you to quickly position your gopro at any angle once your desired angle has been set simply turn the locking knob to tighten the camera in place the locking arm comes equipped with a removable tripod gopro mount for gopro users and a universal 20 screw for attaching other action cameras such as the sony action camera