This U-lock features a Steel ball Click-Combo-Gear system that is user settable with 10,000 possible combinations. Super strong 13-mm hardened steel shackle resists cutting, prying and jacking. Includes Snap lock quick release multi-position mounting bracket and limited lifetime warranty. Other features include: X2P double bolt locking mechanism locks shackle on both sides. TriRadius shackle creates more internal space for more versatility. Co-molded crossbar cover and double rubber coated shackle protects paint. All metal end caps provide additional protection against hits and drops.