RAYSDE BearingsWhy Do Bearings Carry a String of Suffixes?
You have surely seen designations like 6206-2RS1 C3 or 7208 BECBP. The letters and digits after the dash are the suffix — they define the bearing's exact configuration: sealing method, cage material, precision grade, clearance, and more.
Suffix rules differ slightly between manufacturers, but the core logic is the same. Below is the most useful quick-reference table.
Universal Suffixes (Common Across Brands)
| Suffix | Meaning | Notes |
|---|---|---|
| Z | single-side sheet-metal shield | dust protection, not water-proof |
| ZZ / 2Z | both-side sheet-metal shield | most common basic protection |
| RS / -2RS / 2RS1 | single / both-side rubber seal | contact seal, good against water & dust |
| RZ / 2RZ | non-contact rubber seal | lower friction, suited to higher speed |
| C3 | radial clearance greater than normal | for high temp / interference-fit |
| C4 | radial clearance even greater | special high-temperature duty |
| CN | normal clearance (default) | suits most applications |
| /P6 | precision grade P6 | above normal (ABEC-3) |
| /P5 | precision grade P5 | precision (ABEC-5) |
| /P4 | precision grade P4 | high precision (ABEC-7) |
| /P2 | precision grade P2 | ultra precision (spindle use) |
| M | brass cage | heat & corrosion resistant |
| J | stamped steel cage | economy type |
| V | solid glass-fibre reinforced polyamide | low friction, low noise |
Suffixes Specific to Angular-Contact Ball Bearings
| Suffix | Meaning |
|---|---|
| AC (or A) | contact angle 25° |
| B | contact angle 40° (most common) |
| C | contact angle 15° (high-speed precision) |
| DB | back-to-back pair (Dual Back-to-back) |
| DF | face-to-face pair (Dual Face-to-face) |
| DT | tandem pair (Dual Tandem) |
| TN9 | glass-fibre reinforced polyamide cage |
Cross-Reference: Major Manufacturers' Suffixes
The table below cross-references the common suffix systems of major bearing manufacturers (SKF / FAG / NSK / NTN etc.) for technical reference only. RAYSDE can supply equivalent specifications and is not affiliated with any original manufacturer. Always verify codes against the latest manufacturer catalog.
| Meaning | SKF | FAG(Schaeffler) | NSK | NTN |
|---|---|---|---|---|
| both-side rubber seal | 2RS1 | 2RSR | VV / DDU | 2RS |
| brass cage | M | M | M | M |
| polyamide cage | TN9 / TNH | TVP | ET | NP3 |
| larger clearance | C3 | C3 | C3 | C3 |
| high-speed precision | C3 / HCP | HCV / UL | VE / VV | N / NR |
Procurement Tips
- ✅ General machinery: ZZ or 2RS1 + CN clearance covers ~80% of needs.
- ✅ Motors / pumps: prefer 2RS1 (good seal) + C3 (compensates running heat expansion).
- ✅ Machine-tool spindles: require P4/P2 precision + AC/B contact angle + preload.
- ⚠️ Substituting imported brands: match not only dimensions but also the suffix — especially clearance and precision.
Frequently Asked Questions
Why do suffix codes differ between brands?
Each manufacturer standardised its own suffix system when the ISO/ABMA codes did not fully cover a feature. The core logic (seal, cage, clearance, precision) is shared, but the exact letters vary — which is why a cross-reference table is useful.
What does 2RS1 mean?
2RS1 is SKF's code for a both-side rubber contact seal. Equivalent codes from other makers include 2RSR (FAG), DDU (NSK) and 2RS (NTN). They all provide contact sealing against water and dust.
Do I always need C3 clearance?
No. C3 (greater-than-normal radial clearance) is needed when running heat or an interference fit would consume normal clearance — typical in motors, pumps and hot-running machines. Standard applications use CN.
Can RAYSDE supply equivalents to major-brand suffixes?
Yes. Send us your original bearing number and we will quote an equivalent product matching the same clearance, cage and precision specification. RAYSDE is an independent supplier and is not affiliated with any original manufacturer.
🔧 RAYSDE can produce to any suffix specification — whether the original was a European or Japanese manufacturer's code, we can supply an equivalent product. Send us your original number for a same-quality quotation.