The Pawmark BAK-UP Braid Poly Prong Collar Backup is a designed for trainers that utilize multiple collars on dogs in training. The BAK-UP is constructed from 100% USA Manufactured polyester for durable use. The BAK-UP allows you to connect the short couple to a prong or martingale type collar and the longer coupler to a flat buckle, slip or backup collar. Crafted from 100% USA manufactured polyester, USA forged “O” rings and snaps and sewn by hand in our Tennessee office. Accommodates 2 Collars and 1 Leash(not included) Available in Small: 3/8″ x 6″ and Large: 5/8″ x 6