These heavy duty patent pending leads are hand made in Montana. They are made using 1/2" polypropylene cordage which is waterproof and mildew-resistant as well as resistant to most oils, lubricants, and grease. These leads also includes a Quick Release Shackle in place of the traditional brass shackle. The Quick Release Shackle allows the lead to be used as a slip lead, also a traditional 4' lead if clipped directly to the collar.