Kakadu Pet Empire Tracks Dog Leash Coupler, 1/2" x 9-15", Metal (Silver with Black Stitch) The Empire Tracks Adjustable Coupler is designed to comfortably walk two pets together. Clip your lead to the metal O-ring and you are ready to go. Classic base colors with a contrasting stitch design. Made from 100% quality Nylon Measures 1/2" x 9-15"