| Inner Diameter | 4 mm |
| Outer Diameter | 16 mm |
| Thickness | 5 mm |
| Model | 628/4-2Z, 634, 634-2ZC |
| Brand | NACHI |
| Origin | Japan |
High-performance miniature deep groove ball bearings with rich stock, grease or oil lubrication, Z1V1–Z3V3 vibration grades, and 100% on-time delivery. Ideal for precision OEM/ODM applications.