Feature: 1. High Density: Our mountain bike hub is made of six claws with high density, which makes the ratchet teeth bite more tightly and makes the process more stable. 2. Reduced Force Loss: The bike hub can bite into the ratchet after pedaling at a small angle, reducing force loss. 3. Aluminum Alloy Tower Footing: The bike hub is made of aluminum alloy tower base, with a tight structure, high wear resistance and corrosion resistance. 4. Built in Bearings: The bike hub has built in bearings, fluent and effortless, with a front two and back four bearing layout, easy to maintain. 5. Sturdy and Wear Resistant: This bike hub is more sturdy and wear resistant, and the tower base supports for 8‑13 speeds. Specification: Item Type: Bike Front Rear Wheel Hub Material: Aluminum alloy Open Gear Quick Release: Front: Approx. 100mm / 3.94in Rear: Approx. 137mm / 5.39in Barrel Shaft: Front: Approx. 100mm / 3.94in Rear: Approx. 142mm / 5.59in Bearing: 6 Bearings Number of Holes: 32H Speed: Tower footing support for 8-13 speeds. Package List: 1 x Front Wheel Hub1 x Rear Wheel Hub4 x Accessories