Replacement headset bearings for Ritchey headsets. Qty 1 bearing. 45/45 degree angular contact, sealed bearing. Titanium coated for corrosion resistance. Item Specifications: Cartridge Bearing Angle: 45x45, Bearing I.D. (mm): 30.5, Bearing Type: Cartridge, Bearing O.D. (mm): 41.8, Thickness: 8,