| NTN NJ 2304 Bearing | 20 | 52 | 21 | NTN | Cylindrical Roller Bearings |
| ZKL NJ 2304 Bearing | 20 | 52 | 21 | ZKL | Cylindrical Roller Bearings |
| RIV NJ 2304 Bearing | 20 | 52 | 21 | RIV | Cylindrical Roller Bearings |
| NSK 2304 Bearing | 20 | 52 | 21 | NSK | Self-aligning Ball Bearings |
| KOYO 2304 Bearing | 20 | 52 | 21 | KOYO | Self-aligning Ball Bearings |
| NSK NUP 2304 E Bearing | 20 | 52 | 21 | NSK | Cylindrical Roller Bearings |
| FAG NJ 2304 E.TVP2 +HJ2304 E Bearing | 20 | 52 | 21 | FAG | Cylindrical Roller Bearings |
| KOYO NJ 2304 E +HJ 2304 E Bearing | 20 | 52 | 21 | KOYO | Cylindrical Roller Bearings |
| NACHI NJ 2304 E Bearing | 20 | 52 | 21 | NACHI | Cylindrical Roller Bearings |
| SKF NJ2304E+HJ2304E Bearing | 20 | 52 | 21 | SKF | Cylindrical Roller Bearings |