The Surly Ultra New Fixed Rear Disc Hub is a high-durability hub designed for fixed-gear riders who want disc brake compatibility and bolt-on reliability. With a 135mm spacing and 10mm axle, it’s perfect for robust commuting, utility, or touring setups that require a tough, low-maintenance drivetrain. The fixed threading accepts a standard track cog and lockring, ensuring secure engagement with no coasting. Sealed cartridge bearings and a 6-bolt disc mount round out this purpose-built, Surly-strong hub.