... 3.confirm you the quality you need Thrust ball bearing A.products1. Main products: 51100, 51200, 51300, 51400, ... Material: GCr153. Application: Oil drilling machines, screw shaft of oceangoing freighters, combining driving machines, overhead cranes, heavy tower ... machines and so on.B. specifications1. Certification: ISO9001- 2008 Certificate of Origin3. High precision, long life, low noise, high- ...