Mounting gym equipment shouldn't feel like a DIY disaster waiting to happen. Whether it’s a heavy bag that’s too tricky to hang from high ceilings or gym rings and cable pulleys with a mind of their own, the Bells of Steel Utility Shackle Rack Attachment has you covered. quickly mount the Utility Shackle to a 3” x 3” power rack to help keep your attachments secure. Or, mount it on a Utility Arm — maintaining full use of your rack while taking advantage of the often-overlooked side space. This shackle provides a rock-solid grip, making it the ideal solution to help keep your accessories secure and your training space looking sharp. IMPORTANT: works with 3” x 3” racks with 5/8" or 1" holes.