Kryptonite Transit FlexFrame-U Lock BracketCompatible with 13mm and 16mm (round) shaped shackles Mounts quickly and easily and supports the transportation of most common U lock sizes Unique 360 degree rotation provides the ability to micro adjust the lock angle to better fit and align with a bikes frame specific geometry Single point attachment and adjustment design allows for adjustment without removing the bracket completely Heavy duty strap system contours to the shape of the bicycle frame