ID tags are only valuable when they stay attached to your pet, which is why the standard tag hangers that often come with them (either too flimsy to be reliable or too difficult to thread) leave so much to be desired. That's where our S-Biner tag lock comes in. Constructed of stainless steel, with two high quality stainless steel gates and a center lock made of tough, durable plastic. With the S-Biner tag lock, you simply clip the ID tag (or tags) to one gate and the D-ring of your pet's collar or harness to the other. Then, with a simple twist of the center lock, the gates securely lock and stay that way until you twist it open again. Sturdy, water-resistant and ultra-secure, not only does our S-Biner tag lock provide ease of use, but peace of mind. It's simply the best way to keep your pet's ID tags where you want them (on your pet) and also makes adding or changing tags a breeze.