The Scicon Chain Keeper is an indispensable tool for protecting your bike frame from chain damage when the rear wheel is taken off the bike. Ideal for transport in a bike case or bike bag, storage on the wall and cleaning your road, triathlon or mountain bike. The Chain Keeper simply clamps on to the drive side of the rear drop out and ensures the chain stays securely in place. Made out of aluminum, this little helper is mounted in seconds and will last a lifetime.