Zipp Hub Bearing Kit Description: The Zipp Hub Bearing Kit consists of a pair of bearings that will refresh the performance of a worn Zipp hubset. Crafted out of rugged stainless/hardened steels, filled with premium grease, and protected thanks to the low friction seals, these bearings will withstand the elements and use and abuse, and ensure the hubs are performing at their best. Features: Stainless steel construction and low friction seals ensure long life and low rolling resistance Hardened chrome steel ball bearings resist corrosion and pitting Filled with water resistant, high performance bearing grease that prevents over-heating and wear and tear Specifications: Bearing Model: 6903 -or- 61903 Bearing Dimensions (IDxODxW): 17mm x 30mm x 7mm Hub Compatibility: Zipp 76 (Disc Brake) (Front) | Zipp 77 (Disc Brake) (Front) | Zipp 176 (Disc Brake) (Rear) | Zipp 177 (Disc Brake) (Rear) | Zipp 176 (Rim Brake) (Rear) | Zipp 177 (Rim Brake) (Rear) Quantity Per Order: 2 Bearings (Pair)