Zipp Ceramicspeed Bearing Kit|61903 MODIFIED – ZIPP 177 REAR HUB SHELL|61803 MODIFIED – ZIPP 77 FRONT HUB SHELL AND 177 REAR FREE HUB BODY|61903 – ZIPP 30/60 REAR HUB SHELL|61803 X1 61903 X1 – ZIPP SUB-9/SUPER-9 HUB SHELL|61803 – ZIPP 30/60 88 FRONT HUB S

Zipp: For cyclists looking for that extra advantage. Ceramic Speed bearings. Use with ZIPP hubs and free hub driver bodies. Lowest resistance hybrid ceramic, ceramic balls and steel cages available. Measurable wattage savings between 1.5 and 9 watts per be