1.Ball bearing.Roller bearing. hub bearing 2.Material,steel GCR - 15 3.Certificate: ISO 9001:2000 4.Hardness: 62 Deep groove ball bearings description:1 ... ,P4,P2(ABEC1,ABEC3,ABEC5,ABEC7,ABEC9)7. Seal form: OPEN, Z,ZZ,RS,2RS,N,NR Greese/OilAs you requirement ... , motorbikes, textile machines, autos and other areas. deep groove ball bearingWe have Open, Z, ZZ, RS, 2RS,RZ, 2RZ.N,NZ.The ...