Extremely high security chain tried and tested in the streets of new yorkhuge 15 mm round chain links made from triple heat treated boron manganese steel for ultimate strengthnew york padlock with the highest level of security from it39s disc style cylinder including a 16 mm hardened max performance steel shacklehardened double deadbolt design gives additional protection against twist attacksthe reinforced shrouded shell and shackle provides the ultimate in securitylong chain is versatile and