Deep Groove Ball Bearing: 1. ISO 9001:2000 Factory 2. ABEC1, ABEC3, ABEC5 3. Z3,Z4 Deep Groove Ball Bearing:1.Chrome steel material Gcr152.Open, ZZ, 2RS3. High accuracy4. Low noise5. Low weight6. Can be customized according to your needs7. Can provide small & miniature standard and non-standard ball bearings.8.Supply ability: 2,000,000 per month