Stans No Tubes Crest MK4 Wheel Rear 27.5 / 584 Holes: 32 12mm TA 148mm Disc IS 6-bolt Shimano Micro SplineAsymmetric rim design allows for a stronger wheel while offering the easy inflation and Stans trademark unmatched airtight seal. 25mm width optimized for 40mm Gravel tires and up to 2. 3 mountain tires Light and durable 6069 aluminum with welded joint and reinforced spoke bed TECH SPECS Hub Model M PULSE Hub Spacing 148mm Position Rear Rim Material Aluminum Wheel Tire Type Tubeless Ready Axle Type 12mm TA Rim Model Crest MK4 Spoke Type Sapim D Light