Scicon Chain Keeper Ideal for transport in a bike case or a bike bag, the Scicon Chain Keeper is for protecting your bike frame from chain damage when the rear wheel is taken off the bike. It simply clamps on the drive side of the rear drop out and ensures the chain stays securely in place. Made from aluminium, this Chain Keeper can be mounted in seconds and will last a lifetime. Features: Material:CNC Machined AluminiumWeight:0.1kg Buy Scicon Accessories from Chain Reaction Cycles, the World's Largest Online Bike Store.