This #30 nylon snap ring (snap collet) with a soft aluminum shell. The plastic snap rings are ideal for use on furniture, recreational vehicles, manufactures housing, and etc. This nylon back is specially designed to snap onto a durable wood screw or a durable snap when covered. This provides a secured hold with little chance of rust or discoloration. This item is sold in a 1 gross box and includes both backs and shells (144 pcs. of each item).