The Gamber-Johnson 7160-0514 6 in locking slide arm with 3/8 in stud. The entire arm can rotate around 360 deg. with locking points at every 15 deg. The locking slide arm can slide up to 5.5 in form the center of the pole. It mounts on any upper pole, complete pole, low-profile brackets, center pole, or directly to any flat surface.