Mammoth Black 12 mm Hexagon Motorcycle Chain & Lock The Mammoth Black 12 mm Hexagon motorcycle chain & lock is a no nonsense heavy duty motorcycle security solution for riders looking to keep their pride and joy secure. The chain is made with 10 mm hardened steel square links, meaning you can rest assured that your bike is in safe hands while unattended. A protective fabric sleeve ensures that your bike paintwork is safe from scratches. Available in two lengths to suit any riders setup and needs. Motorcycle Chain & Lock Features: Ultimate bike security! 12 mm hexagon section chain. 11 mm hardened steel closed shackle lock. Protective textile outer sleeve protects paintwork and rims. 1.8 M & 1.0 M lengths available.