Bearing suffix dictionary: 2RS, ZZ, C3, K, E, W33 and more

Suffixes are everything after the basic bearing number: the “-2RS-C3” in 6205-2RS-C3 or the “E-K-C3” in 22216-E-K-C3. They describe how a particular bearing differs from the basic design without changing its boundary dimensions.

Read this first. Suffix systems are not standardised across manufacturers. The meanings below are typical, widely used conventions — not definitions. The same letter can mean different things for different makers, product generations or bearing types. Always confirm with the manufacturer’s own designation system before ordering or substituting.

For how suffixes fit into the full number, see how to read a bearing number. To split a full designation automatically, use the bearing number decoder.

Closures: shields and seals

Guide: sealed vs shielded bearings.

Internal radial clearance

The micrometre values behind each class depend on bearing type and size. Guide: C3 clearance explained.

Cage design and material

Polyamide cages have temperature limits and are sensitive to some lubricants; brass and steel cages behave differently under shock and high speed. Treat cage material as a real attribute, not cosmetic.

Bore

Internal design and contact angle

Contact angle suffixes matter: a 7205 B and a 7205 AC have the same envelope but different axial load behaviour and stiffness.

Features and lubrication

Precision (tolerance class)

Precision classes describe dimensional and running accuracy. They are independent of clearance: a bearing can be P6 with C3 clearance.

Putting it together

For catalog and data teams

Suffix strings are among the hardest fields to compare across suppliers, because two different strings can describe the same feature and one string can hide several features. Parse them into explicit attributes — closure_type, closure_sides, internal_clearance, cage_material, bore_shape, contact_angle, precision_class — and keep the original suffix next to the parsed values. Mark anything you could not parse as unresolved rather than guessing. Our normalization page shows this pattern.

Apply it

Decode a full number with the bearing number decoder, or look up the base size on the bearing reference. Need suffixes normalized across a whole supplier catalog? Contact us.