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 s