We're big fans of 12x142mm thru-axle systems. For many full suspension designs, the extra stiffness of the thru-axle over a standard quick release provides a seat-of-the-pants difference in how the rear end behaves through heavy trail chatter or when standing hard on the pedals. This Shimano XTR M988 12x142mm Thru-Axle uses an aluminum axle shaft with a fluted nut on the right side and a quick-release style tension lever on the left.