At a glance
6203
A complete basic designation identifying a common deep-groove size before its optional suffixes.
Use the full number and suffix to retrieve the relevant dimensional and performance record.
203
May be shorthand, a legacy designation or part of another manufacturer's product code.
Use only after identifying the manufacturer, complete marking and dimensions.
Key differences
Typical design distinctions. The complete designation and current product specification take precedence.
Swipe the table horizontally to see both options →
| What to compare | 6203 | 203 |
|---|---|---|
| Identification | Recognised complete basic designation | Potentially incomplete or system-specific |
| Nominal bore | Commonly 17 mm | Must be verified |
| Nominal outside diameter | Commonly 40 mm | Must be verified |
| Nominal width | Commonly 12 mm | Must be verified |
| Closure and clearance | Specified by suffix or product record | Not determined by 203 alone |
| Replacement decision | Use verified dimensions and suffix | Establish the exact cross-reference first |
Before you choose
- A short marking on a seal or packaging may not be the full bearing designation.
- Do not convert all records containing 203 into 6203.
- Measure dimensions and record the maker before searching an ambiguous old part.
Check the actual model
Search a full designation, inspect its technical data, then compare candidate records. Similar names or dimensions do not guarantee interchangeability.
Filters show recorded catalogue attributes. Open each candidate to confirm its exact specification.
A few things worth clarifying
Is 203 the same as 6203?
It can be used that way in a particular system, but the bare number is insufficient to guarantee equivalence.
What should I measure?
Bore, outside diameter and total width, then inspect markings, seals, grooves and shoulders.
Reference basis & limits
- NSK — 6203 single-row deep groove ball bearing product data
- NSK — Bearing Designation Systems, March 2024
Independent explanatory content; not a manufacturer endorsement or approval of a replacement. Verify current product data, fits, lubrication and operating conditions before applying a comparison.