These Hog Rings are only for use with the BNHRT Bird Net Hog Ring Tool. Hog Rings are used to attach netting to the cable perimeter. Hog Rings can also be used to attach net accessory items such as net zippers and patch minor tears in netting. Prior to being crimped with a Hog Ring Tool, rings come in a ‘C’ shape. Once the ring is crimped the shape will change to an ‘O’ ring. Hog Rings have sharp points to allow rings to pierce surfaces when crimped. Hog Rings come in a box of 2,500 rings with the option of galvanized steel or stainless steel material.