RockyMounts DriveShaft HM is our locking 12mm/15mm/20mm thru-axle (including BOOST 110) bolt on system for trucks, SUV's, and trailers. Comes with a flat mounting surface designed for "do it yourself" bolt on installation. Designed with a wide mouth opening to easily load your bike and a T-Bolt that adjusts for a tighter hold so the thru-axle cannot be unscrewed. Lock and keys included. Mounting hardware not included. The holes accept M6 or 1/4" bolts, depending on your application (wood, steel, screws, bolts), etc, you will need to get the correct bolts for your application.