Features1More Accurate Shifting: Mountain bike hub set adopts high accuracy bearings, which reduce the yaw when the freewheel and flywheel rotate, and the shifting is more accurate 2Built in Bearing: The 4 bearing bike hub has a built in bearing, which is glossy and labor saving, meeting your needs 3Bearing Accessories: The bike hub set is a mountain bike hub 4 bearing sealed bearing accessory with 32 hole 9 to 13 speed center lock hub 4Aluminum Alloy: The main body of the 32 hole bike hub set is made of aluminum alloy, which is not easy to corrosion, compact and durable 5Bearing Layout: The 4 sealed bearing bike hub adopts a bearing layout with two fronts and four rears, which is easy to maintain and more effortless to rideSpecificationItem Type:BikeHubSetMaterial: Aluminum AlloyStrip Hole: Front and Rear 32HBearing: First 2, Last 4Front Hub Specifications:Quick Release: Approx. 100 x 9mm/3.9 x 0.4inThrough Axes: Approx. 100 x 15mm/3.9 x 0.6inRear Hub: Specifications:Quick Release: Approx. 135 x 9mm/5.3 x 0.4inThrough Axes: Approx. 135 x 12mm/5.3 x 0.5inThrough Axes: Approx. 142 x 12mm/5.6 x 0.5inPackage List1 x Front Hub1 x Rear Hub2 x Quick Release4 x Quick Release End Covers2 x Through Axes End Covers1 x Washer