ENVE Composites M5 Pro Rear Wheel - 29" 12 x 148 Center-Lock XD Innerdrive 80pt BLKENVE Composites M6 Rear Wheel 29" 12 x 148 Center Lock Micro Spline Innerdrive 80pt Black. The M5 Pro marks a new era in M Series cross country wheels raising the bar for speed efficiency and toughness. It is the result of a more than 4 year development project during which ENVE worked closely with its professional athletes to create something that would give the fastest endurance athletes an edge. Unique front and rear rim construction combined with