Project 321 checks all the major boxes with their latest Disc Rear Hub. It features incredibly low drag, quiet pawls, form tapped rotor bolts, XD and HG freehub bodies, and Boost as well as 12x142mm Thru Axel spacing. Like all their products, the Rear Disc Hub is made in Fresno, CA. All the Project 321 rear hubs are under 300 grams and easily belong in the same conversation with names like Chris King, Industry 9, and other high-end hub makers. Discover what die-hard Lefty users have known for a long time, check out Project321 today.