| SKF 2304M Bearing | 20 | 52 | 21 | SKF | Self-aligning Ball Bearings |
| FAG NU2304E Bearing | 20 | 52 | 21 | FAG | Cylindrical Roller Bearings |
| KOYO NUP2304R Bearing | 20 | 52 | 21 | KOYO | Cylindrical Roller Bearings |
| SKF NJ2304E+HJ2304E Bearing | 20 | 52 | 21 | SKF | Cylindrical Roller Bearings |
| ZKL NU 2304 Bearing | 20 | 52 | 21 | ZKL | Cylindrical Roller Bearings |
| RIV N2304 Bearing | 20 | 52 | 21 | RIV | Cylindrical Roller Bearings |
| FAG 32304 A+T2F D020 Bearing | 20 | 52 | 21 | FAG | Tapered Roller Bearings |
| KOYO NJ2304R Bearing | 20 | 52 | 21 | KOYO | Cylindrical Roller Bearings |
| KOYO NU 2304 R Bearing | 20 | 52 | 21 | KOYO | Cylindrical Roller Bearings |
| NACHI NU2304E Bearing | 20 | 52 | 21 | NACHI | Cylindrical Roller Bearings |