ONGUARD 5018HD Beast Chain Bicycle Lock (160cm x 11mm) Highest security rating for maximum protection in high crime areas Massive hex link steel chain with titanium reinforcements are almost impossible to cut or break Beast Locks have Quattro or Dual Lock mechanisms featuring dual lockdown protection where hardened steel pins engage Locks also feature rubber end caps and vinyl coatings to protect finish Reinforced sleeve over crossbar and cylinder for additional security Both ends of the shackle creating a redundant locking system for added security