The Kryptonite Keeper 785 is a very strong and durable chain lock made of hardened 7 mm manganese steel links. Nylon chain surface, vinyl coating on the lock to prevent wheel damage.Newly available in 4 colors ( Black, Grey, Red and Purple. 7mm square chain links made of 3T manganese steel. New more durable DEADBOLT mechanism. High security disc lock body. Package includes 2 ergonomic keys. Waterproof nylon sleeve protects against scratches. Key Safe program - if keys are lost, send 1st pair of standard replacement keys free of charge. (registration required) Dimensions: 85cm chain length Protection level: 5/10