Superior protection for medium to high crime areas. X4P Quattro Locking Mechanism for four-sided protection. Hefty 14mm (0.55″) hardened steel TriRadius shackle resists cutting, prying and jacking while providing more internal space for locking versatility. New crossbar and shackle coatings protect finishes. provide increased locking versatility for securing bicycles and scooters. Shackle Dimensions: 115mm x 229mm (W x H x Diam) (4.53″ x 9″) x 14mm (0.55″) D.