The Springer Dog Exerciser is used by over 600,000 dog-loving bicyclists, mushers, and K9 corps around the world. It uses a low-mounted, heavy-duty steel spring to absorb up to 90% of the force of a dog’s unexpected tugs, which allows bike riders to keep their balance, while also protecting their dogs from traffic, pedals, and wheels. Its patented safety release frees your dog instantly if he/she gets caught around a tree or hydrant. The safety release is attached to a sturdy 18” rope cord that is knotted through the appropriate hole, depending on your dog’s size and strength. Use the largest end for dogs that are strong pullers. Manufactured in Norway, it’s super easy to install and you have the option to exercise two dogs simultaneously with the Springer Extra Arm Kit, which is sold separately. The attachment fits most regular, touring, and mountain bikes. Harness not included, so please be sure to use a harness that is appropriate for your dog’s breed.