Burgtec Transition 171mm Rear AxleClean and Simple is always best. Leverless design for added security and clearance for when situations get tight. These super tough axles tighten up with a 6mm Allen key. They feature a get out of jail 6mm Allen key on the drive side of the axle if you manage to round the non drive side. Dropout Bolt is also provided. Constructed from 7075 Aluminium and made to the manufacturers exact specifications. Fits: All Transition 12 x 148 Bikes except those