Maximum security U-lock for high theft areas. Extra thick 16 mm case-hardened Kryptonium steel shackle resists cutters and leverage attacks. Cross bar is shielded by a hardened Kryptonium steel sleeve in a double crossbar design for double security. High security anti-pick disc-style cylinder with patented double deadbolt lock. Flat key with integrated sliding dustcover protects the cylinder. The Transit FlexFrame-U mounts quickly and easily and supports the transportation of the most common u-lock sizes. The Flex Frame-U fits bicycle frame tubing 25mm to 80mm whether round, oval, triangular or square shapes. The mounting system allows for 360 degree rotation providing the ability to micro-adjust the lock angle to better fit and align with a bike frames specific geometry. Approved to Gold Sold Secure standard. Approved to Thatcham CAT3.