625 bearing dimensions
A 625 bearing is 5 mm bore × 16 mm outside diameter × 5 mm wide (0.197 × 0.630 × 0.197 in). The sealed version is 625-2RS; the shielded version is 625-ZZ.
625 at a glance
Boundary dimensions in millimetres and inches, and the common closure designations.
- Bore, d
- 5 mm 0.1969"
- Outside diameter, D
- 16 mm 0.6299"
- Width, B
- 5 mm 0.1969"
- Section height, (D − d)/2
- 5.5 mm 0.2165"
- Series
- 62 series light
- Bore code
- 5 Under 10 mm bore the last digit is the bore itself: 5 = 5 mm
- Sealed, both sides
- 625-2RS
- Shielded, both sides
- 625-ZZ
- Open
- 625 no closures; any version may add C3 for extra internal clearance
Reading the number 625
Every deep groove ball bearing number follows the same pattern: type, dimension series and bore code, then suffixes.
Seals, shields and suffixes
Suffixes add closures and internal clearance. They do not change the boundary dimensions: a sealed and an open bearing of the same number are interchangeable in size.
| Suffix | Meaning | 625 example |
|---|---|---|
| Open (no suffix) | No seals or shields. Can be relubricated, or run in an oil bath; the housing needs its own seal against dirt. | 625 |
| Z | One metal shield, on one side only. | 625-Z |
| ZZ, 2Z | Metal shields on both sides. Non-contact, so low friction; keeps out larger dirt. Usually greased for life. | 625-ZZ |
| RS | One rubber contact seal, on one side only. | 625-RS |
| 2RS, 2RS1, 2RSH, 2RSR, DDU, LLU | Rubber contact seals on both sides. Better than shields against fine dirt and splashing water, with a little more friction. Usually greased for life. | 625-2RS |
| C3 | Radial internal clearance greater than normal (CN). Used with tight shaft or housing fits, or where the inner ring runs hotter than the outer ring. | 625-2RS C3 |
625 in other brands
The sealed and shielded versions as each maker writes them. All share the same boundary dimensions.
| Maker | Sealed both sides | Shielded both sides |
|---|---|---|
| SKF | 625-2RSH | 625-2Z |
| FAG (Schaeffler) | 625-2RSR | 625-2ZR |
| NSK | 625DDU | 625ZZ |
| NTN | 625LLU | 625ZZ |
| Koyo (JTEKT) | 625-2RS | 625ZZ |
| Timken | 625-2RS | see catalogue |
Seal designs and suffixes vary by maker, size range and product generation, for example contact versus low-friction seals. Confirm the exact designation in the maker's catalogue before ordering.
Same 5 mm bore, other series
Bearings that fit the same shaft. A heavier series carries more load in a bigger housing bore; a thin-section series saves space and weight.
| Bearing | Series | OD | Width | Section | vs 625 |
|---|---|---|---|---|---|
| 605 | extra-light | 14 mm | 5 mm | 4.5 mm | −2 mm OD, same width |
| 625 | light | 16 mm | 5 mm | 5.5 mm | this bearing |
Miniature bearings
Common questions
What size is a 625 bearing?
5 mm bore, 16 mm outside diameter and 5 mm wide, which is 0.197 × 0.630 × 0.197 in.
What does 2RS mean on a 625 bearing?
625-2RS has rubber contact seals on both sides. 625-ZZ (also written 625-2Z) has metal shields on both sides. Both have the same 5 × 16 × 5 mm dimensions.
Is 625-2RS the same as 625-ZZ?
They are the same size and interchangeable in a housing. The sealed 625-2RS keeps out fine dirt and water better; the shielded 625-ZZ runs with less friction.
What is the SKF equivalent of 625-2RS?
SKF writes it 625-2RSH; FAG 625-2RSR, NSK 625DDU, NTN 625LLU and Koyo 625-2RS. Check the maker's catalogue for the exact seal type.
What does the number 625 mean?
6 is the deep groove ball bearing type, 2 is the light dimension series, and under 10 mm bore the last digit is the bore itself: 5 = 5 mm.
Which bearings have the same bore as 625?
605 also have a 5 mm bore, with different outside diameters and widths.