Like Ceramic Hybrid, Zero Ceramic use a combination of ceramic (Silicon Nitride - Si3n4) balls andÊsteel races, except they are of higher GradeÊ3 quality. The races are also black oxide treated and ground toa mirror finish which prevents corrosion and provides near perfectÊefficiency and tolerances.Bearing Code: 6001Dimensions: 12mm x 28mm x 8mmABEC: 5Grade: 3Seals: VVGrease:ÊKyodo Yushi PS-2Application:ÊHubs, Bottom BracketsWeight: 17.74gFor further detailed information on Enduro bearings clickÊhere