6304 bearing: 20 × 52 × 15 mm
Bearings › 6304
A 6304 is a deep groove ball bearing, 20 mm bore, 52 mm outside diameter, 15 mm wide. Variants: 6304-2RS (rubber sealed), 6304-ZZ (metal shields), 6304 open.
| Bore | 20 mm |
|---|---|
| Outside diameter (OD) | 52 mm |
| Width | 15 mm |
| Dynamic load rating C | 16.8 kN |
| Static load rating C0 | 7.8 kN |
| Limiting speed | 19 000 r/min |
| Weight | 0.139 kg |
Ratings and weight: SKF product page, skf.com, read 2 Oct 2026, designation 6304. Limiting speed as SKF gives it.
Open 6304 in BenchsmithAdd to order list
What the number means
6 | Deep groove ball bearing |
3 | Medium series |
04 | Bore 04 × 5 = 20 mm |
Ask for
- 6304-2RS: rubber sealed both sides. Other brands: SKF 6304-2RSH, FAG 6304-2RSR, NSK 6304DDU, NTN 6304LLU, Koyo 6304-2RS.
- 6304-ZZ: metal shields both sides. Other brands: SKF 6304-2Z, FAG 6304-2ZR, NSK 6304ZZ, NTN 6304ZZ, Koyo 6304ZZ.
- 6304: open, no seals or shields.
Add C3 for electric motors and anything that runs hot.
About the 63 series
Same bore as the 62, but a bigger OD and wider. Heavier load, same shaft. You'll find them in pumps, compressors and the drive end of bigger motors.
If a 62 keeps failing and the housing has room, a 63 is the usual upgrade. Check the housing bore first; it won't fit a 62's seat.
Same bore, different size
One size up or down
Every bearing 20 × 52 × 15 mm: 20 × 52 × 15 mm bearings. Measured a bearing with no number on it? Type the bore, OD and width into Benchsmith → Find → Bearing.