Miniature ball bearings are designed for compact applications, offering smooth operation, low friction, and low maintenance. Ideal for high-speed and precision requirements. Common applications include robotics, medical equipment, electronics, aerospace and aviation, automotive, precision instruments, hobby and RC models, and more. Available 52100 chrome steel or 440C stainless steel, Z1V1 to Z4V4 noise and vibration classes, P0 to P5 tolerance precision.
| d | 1.2 mm | Bore diameter |
| D | 4 mm | Outside diameter |
| B/B1 | 1.8 mm | Width |
| d1 ≈ | 2.15 mm | Shoulder diameter inner ring |
| D1 ≈ | 3.05 mm | Shoulder diameter outer ring |
| r | 0.1 mm | Chamfer |
| 6 pcs | Ball qty | |
| 0.7938 mm | Ball diameter | |
| ≈m | 0.1 g | Weight |
| Cr | 138 N | Basic dynamic load rating |
| C0r | 35 N | Basic static load rating |
| 110000 r/min | Max speed (Grease) | |
| 130000 r/min | Max speed (Oil) | |
| P0(ABEC-1) | Tolerane | |
| CN | Clearance |
| Open | Sealing | |
| None | Locating feature outer ring | |
| 52100 | Ring Material | |
| 52100 | Ball Material | |
| SPCC | Cage Material |
| NMB | NHBB | NSK/ISC | NTN | BARDEN | RMB | MPB(TIMKEN) | SKF | ADR | GRW | EZO | DYNAROLL | FAFNIR | FAG | Gost | others |
| R-412 | MR41X | BC1.2-4 | MR41X |
