The Springer Bike Attachment makes it possible for you to enjoy biking and exercising with your dog at the same time. With the clamp attachment it is so easy to install with only an adjustable wrench. This attachment was constructed with safety in mind. There is a safety release which frees your dog instantly without discomfort to either your or your dog. The Springer's low mounted coil spring absorbs and reduces the dog's tugs and pulls, makeing it easier to keep balance. It also, holds the dog gently but firmly in place beside the bike, keeping the dog from interfering with the pedals or wheels. The most important feature is that it allows both hands the freedom for the bikes handle bars. Springer installs on either side of most standard ladies' and men's bikes. Between trips Springer may be mounted or dismounted in two seconds, using only the tip of your finger. Most dogs learn to run with Springer just after a few minutes. This is a great way to relax and enjoy your bike ride while takeing your dog along. Hundcycler Harness sold seperately.