Mammoth Black 10 mm Square Motorcycle Chain & Lock (1.8 M) The Mammoth black 10 mm square 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 10mm 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. Motorcycle Chain & Lock Features: 10 mm square section chain. 1.8 m length. Protective textile outer sleeve protects paintwork and rims. 11 mm hardened steel closed shackle lock.