Boost grip strength by hanging on for dear life. Helps with rock climbing, weightlifting, ninja training, farmers walks, sled pulls, etc. Cannon balls are three inches in diameter. Made from cast iron. Mounts to any pull up bar or rig. Black color. Sold as a pair. Push your grip to a new level with the CFF Cannon Ball Grip. Coming in at a diameter of 3”, you will have to work to hold on. If you want a stronger grip, here is where you need to start. The Pit Bull Cannon Ball Grip Set will strengthen your hand grip, as well as forearms. This will enhance many aspects of training such as increasing grip strength for rock climbing, weightlifting, sled pulling, resistance band pulls, farmers walks, and more. This product comes with two straps and two steel carabiner clips for mounting.