Surly Ultra New Disc Front Hubs.6061-T6 forged hub shell (same as the Surly New); 6901 bearingsAxle is quick release and bolt-on compatibleStainless 6mm bolts are included; quick release skewer is NOT included4130 CroMoly axle and stainless cones; agressive knurling on cones and bolt caps for reduced slippageNew axle/cone system uses uses a specific shouldered axle that allows the hubs to be completely adjustment free and simple to serviceItem SpecificationsColorBlackIntended UseMountainHub Drilling36spokesHub/Brake Compatibility6-Bolt DiscFront Wheel TypeMountainFront Hub Spacing100mmFront Axle Type9x1Skewer IncludedNoDefined ColorBlack