This is a very versatile leash. You can attach the bolt snap to either of the two O-rings or D-ring to make the leash different lengths. The O-rings are large enough to slip the bolt snap through to double the lead. It can be used over your shoulder to work the dog off-leash, but still have the dog close for quick correction.
The lead attaches to your dog's collar with a quick release, french scissor snap.