Kryptonite Transit FlexFrame U-Bracket Mounts quickly and easy Supports the transportation of the most common size u-locks Compatible with 13mm & 16mm round shaped shackles 360 DEGREE ROTATIONallows for the ability to micro-adjust Heavy-dutySOFT STRAP SYSTEMcontours to bike frame Product dimensions: Fits bicycle frame tubing 25mm to 80mm whether round, oval, triangular or square shapes Unique 360 degree rotation provides the ability to micro-adjust the lock angle to better fit and align with a bike frame's specific geometry Mounts quickly and easily and supports the transportation of the most common u-lock sizes. Fits bicycle frame tubing 25mm to 80mm Automotive grade hex bolt Knurled TugBlock increases holding power Strap that includes stiched-in rubber shim-easier for mounting Works with 13mm to 16mm lock shackle sizes