... Retainer):Brass cage,nylon cage,steel cage3. Quality level:Reach the same level as Japanes and European bearings4. Delivery time: ... high speed,long life6.Application:home appliances.low noise and high speed electric motors,auotomotive components,pups,machinery,Bicycle7. ... material : GCr15_China/(AISI) 52100_American/(DIN)100Cr6_Germany(Chrome steel)12.Vibration and noise level: Z1,Z2,Z3,2V2,2V3,Z2V2, ...