Keeper 712 Integrated ChainDescription The Kryptonite Keeper 712 Integrated Chain Lock offers compact yet durable protection using hardened 7 mm four sided 3T manganese steel links in a 4 ft (120 cm) integrated chain design. The patent pending end link and deadbolt system removes traditional weak points to enhance security. A high security disc style cylinder resists picking and drilling, while the weather resistant nylon sleeve protects your bike frame from scratches and the