A lightweight integrated chain in the Keeper line of Kryptonite security products, the Keeper Integrated Chain is a hardened triple heat-treated boron manganese steel chain made with 7 mm four-sided links.The Keeper Integrated Chain secures with a new integrated lock head. The end pin-link design secures the chain with a hardened deadbolt and offers great holding power against attacks. The high security disc-style cylinder is pick and drill resistant. Chain links are enclosed in a nylon-webbing sleeve to protect paint from scratches. Each chain comes complete with 2 ergonomic 'I' keys. The new 'I' key makes opening a disc-style cylinder much smoother