Specifications Hign-concerned Chemical:None Type:MTB Bike Hubs Size:148mm Number of Holes:28 holes Axle:THRU Freehub:XD Position:Front + Rear Braking System:Disc Brake Spoke Hole:20 - 28 Material:Aluminum alloy Category:Bearing Hub Hub Hole Number:28 Holes M180 52T Ratchet Bicycle Hub 6-Bolt Disc Brake 28Hole Straight pull Spoke Sealed Bearing HG/XD/MS Hub body 142X12 148X12 Dear friends: This Bicycle hub is specially used for XC Mountain Bike. No brandModel: M180 ( MTB hub ) Color: Black Brake Interface: 6-Bolt Brake Number of holes: 28Holes Spokes type: Straight Pull Spokes Material: 7075 aluminum alloy Ratchet: 52T Ratchet Bearing No brandBearing quantity: Front hub: * 2Pcs Rear hub: * 4Pcs Axle system: QR / THRU Axle Built-in Dimension: Front Freehub: 100X9mm 100X15mm 1101X15mm Rear Freehub:135X10mm 141X10mm 142X12mm 1481X12mm Weight: 358g ( HG QR 1pair ) Cassette interface: Shimano HG (MTB) Cassette interface: SRAM XD Cassette interface: Shimano MS (Micro Spli*e) 52T ratchet introduce Material: 20CRMOTI Center hardness: HRC55 Surface hardness: HV2000 Limit torque: 400NM Fatigue resistance: 100,000 times (250NM) Warranty: 2 years or 30,000 km Example: ;F;=Front ;R;=Rear