| KOYO 2304 Bearing | 20 | 52 | 21 | KOYO | Self-aligning Ball Bearings |
| NSK NJ2304E+HJ2304E Bearing | 20 | 52 | 21 | NSK | Cylindrical Roller Bearings |
| KOYO NJ 2304 Bearing | 20 | 52 | 21 | KOYO | Cylindrical Roller Bearings |
| NSK 2304 Bearing | 20 | 52 | 21 | NSK | Self-aligning Ball Bearings |
| STEYR NJ 2304 E Bearing | 20 | 52 | 21 | STEYR | Cylindrical Roller Bearings |
| FAG 32304A+T2FD020 Bearing | 20 | 52 | 21 | FAG | Tapered Roller Bearings |
| SKF NJ 2304 E CP* Bearing | 20 | 52 | 21 | SKF | Cylindrical Roller Bearings |
| SKF NUP 2304 E Bearing | 20 | 52 | 21 | SKF | Cylindrical Roller Bearings |
| NSK NJ2304E Bearing | 20 | 52 | 21 | NSK | Cylindrical Roller Bearings |
| RHP 2304 Bearing | 20 | 52 | 21 | RHP | Self-aligning Ball Bearings |