MK0 items represent a refined approach to component engineering. All items are made in small batches and feature premium raw materials, labor-intensive CNC machining, and a new design language. The result is components with a refreshed aesthetic and increased performance gains. MK0 Centerlock Rotor Lockrings with an internal spline feature a new design language and an exclusive color. For this new aesthetic, each lockring spends extra minutes in a CNC lathe, before undergoing thorough QC inspection, anodizing in the new Shadow Gray color, and branding before it can be installed on a hub. The extra machining and new profile of the MK0 Centerlock Rotor Lockrings with an internal spline have meaningful gains. Compared to the non-MK0 design, these spend 3x the time in the CNC lathe, resulting in a 35% reduction in weight without compromising strength and durability. Wolf Tooth MK0 Centerlock Rotor Lockrings - External Spline secure a centerlock brake rotors on centerlock hubs. It is a complete redesign of the original Wolf Tooth Centerlock Rotor Lockring, with special consultation with Team Visma Lease A Bike. Extra CNC machining time enabled a 35% reduction in weight compared the original lockring design. The featherweight profile aligns with other MK0 products with a spoked design and visible machine paths. MK0 Centerlock Rotor Lockrings – External Spline are made with 7075-T6 aluminum and machined at Wolf Tooth in Minnesota, USA. Sold Individually. Compatibility - Compatible with 12mm, 15mm, and 20mm thru axles and QR - Torque to 40Nm - Install with a 44-16 BB tool or Wolf Tooth Pack Wrench - Wolf Tooth Centerlock Rotor Lockrings – External Spline use the industry standard 4 mm flange and 44 mm outer diameter, which is compatible with all mountain bike fork/frames and many road bike fork/frames. However, there are some road bike fork/frames that require a special thinner lock ring. Wolf Tooth has a Centerlock Rotor Lockring - Internal Spline that is thinner. Please verify clearance on your bike before ordering.