Surly’s Ultra New Rear Hub is ready for singlespeed mayhem. This gorgeous hunk of aluminum has the capability you need with reliable sealed bearings. It’s available with threads for fixed cogs or freewheels, so you can set up the drivetrain of your dreams. Plus, this hub’s 135mm width fits most MTB frames and the hollow chromoly axle provides a flex-free ride as well as simple quick-release skewer compatibility.