604 Bearing
Bore (d) 4 mm
Outside diameter (D) 12 mm
Width (B) 4 mm
Inches (bore × OD × width) 0.1575 × 0.4724 × 0.1575″
Deep-groove ball bearing, miniature (60x) series. Seal/shield suffixes (ZZ, 2RS, …) change the closures, never these dimensions — a 604-ZZ and 604-2RS are the same size.
What the number means
- 6 — deep-groove ball bearing
- 0 — miniature (60x) series
- 4 — bore in mm (4 mm)
Neighboring sizes (miniature (60x) series)
Same bore, other series
Fits the same 4 mm shaft with a different OD/width envelope and load capacity.
- 624 — 4 × 13 × 5 mm (miniature (62x))
Common suffixes on a 604
| Suffix | Meaning |
|---|---|
| ZZ / 2Z | steel shields both sides (metal, non-contact) |
| Z | steel shield, one side |
| 2RS | contact rubber seals both sides (SKF 2RS1, NSK DDU, NTN LLU) |
| RS | contact rubber seal, one side |
| 2RZ | low-friction non-contact seals both sides (NSK VV, NTN LLB) |
| C3 | radial internal clearance greater than Normal (common in motors) |
| C2 | radial internal clearance smaller than Normal |
| NR | snap ring groove in the outer ring, with snap ring |
| P6 / P5 / P4 | ISO precision classes (≈ ABEC 3 / 5 / 7) |