Key Features:Bicycle security for moderate to high crime areas, with a standard length shackle13 mm hardened Kryptonium steel shacklePatented deadbolt locking mechanism for extensive holding powerHigh security disc style cylinderReinforced sleeve over crossbar and cylinder provides enhanced security protectionReinforced internal housing increases resistance to twisting and leverage type attacksOffset key location and overhead cam locking mechanism resists leverage attacksPatented, easy to use, high security Bent Foot designAnti-Rattle bumpers keeps the shackle snug against the crossbar and prevent unnecessary noise2 keysThe Transit FlexFrame-U mounts quickly and easily and supports the transportation of the most common u-lock sizesThe Flex Frame-U fits bicycle frame tubing 25mm to 80mm whether round, oval, triangular or square shapesThe mounting system allows for 360 degree rotation providing the ability to micro-adjust the lock angle to better fit and align with a bike frame specific