Verified by Rachel Mayfield , Supply Chain Analyst - July 2026
Photo by Marcelo Avila on Pexels The 6204 is a single-row deep groove ball bearing with a 20 mm bore, 47 mm outside diameter and 14 mm width (20x47x14 mm). Those boundary dimensions are set by ISO 15, so a 6204 from SKF, FAG, NSK, NTN, Koyo or any budget brand is dimensionally interchangeable - the differences are in materials, precision grade, internal clearance and seal design, not size.
6204 bearing dimensions
Property Value Standard Bore diameter (d) 20 mm ISO 15 Outside diameter (D) 47 mm ISO 15 Width (B) 14 mm ISO 15 Bearing type Single-row deep groove ball bearing ISO 15 Dimension series 6200 (medium) ISO 15
Always measure a worn bearing before ordering if the number is unreadable: bore with calipers on the inner ring, outside diameter across the outer ring, and width across either ring face. 20x47x14 mm identifies the 6204 uniquely among common metric sizes.
What the suffixes mean (6204ZZ, 6204-2RS, 6204-C3)
Suffix Meaning When to choose it ZZ / 2Z Metal shield both sides Non-contact, low friction, keeps debris out. Not washdown-proof. 2RS / 2RS1 / DDU / LLU Rubber seal both sides Contact seals, best dirt and moisture exclusion, slightly more friction. Z / RS Shield or seal one side only Open on the other side - used where relubrication is needed. Open (no suffix) No seals or shields For housings with their own sealing and external lubrication. C3 Extra internal clearance For motors and anywhere the inner ring runs hotter than the outer. 2RS-C3 Sealed + C3 clearance The standard electric-motor spec.
Brand equivalents for the 6204
Every major manufacturer makes the 6204. The seal and shield codes differ by brand but the bearings interchange directly:
Brand Shielded version Sealed version SKF 6204-2Z 6204-2RSH FAG (Schaeffler) 6204-2ZR 6204-2RSR NSK 6204ZZ 6204DDU NTN 6204ZZ 6204LLU Koyo (JTEKT) 6204ZZ 6204-2RS
Load ratings: check the maker's catalogue
Dynamic (C) and static (C0) load ratings for the 6204 differ between manufacturers and between standard and premium ranges, so MLC does not publish a single figure. Look the value up in the manufacturer's own catalogue for the exact variant you are buying - SKF, Schaeffler medias, NSK and NTN all publish free online catalogues with per-variant ratings, limiting speeds and grease specifications.
Where the 6204 is used
The 6200 (medium) series is the most widely stocked general-purpose series. Typical 6204 applications include electric motors, gearboxes, pumps, fans, conveyor rollers, power tools and general machinery - anywhere a rotating shaft of 20 mm needs simple radial support with modest axial capability.
Fitting basics
For a rotating shaft (the normal case), fit the inner ring with a light interference (k5/k6 shaft tolerance for most machinery) and the outer ring with a close clearance fit (H7 housing). Press only on the ring you are fitting - pressing the outer ring through the balls to seat the inner ring is the fastest way to brinell a new bearing. For sealed 2RS variants, no relubrication is needed or possible; the factory grease fill is for life.
Need this bearing? Send the designation and quantity and Acumen Seals & Pumps will price it, including sealed, shielded and equivalent options.
Get a quote for 6204 Bearing Dimensions: 20x47x14mm, Seals + Equivalents
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