| RHP 2304 Bearing | 20 | 52 | 21 | RHP | Self-aligning Ball Bearings |
| NACHI NJ 2304 E +HJ 2304 E Bearing | 20 | 52 | 21 | NACHI | Cylindrical Roller Bearings |
| NACHI NU 2304 E Bearing | 20 | 52 | 21 | NACHI | Cylindrical Roller Bearings |
| NSK NSK2304TN Bearing | 20 | 52 | 21 | NSK | Self-aligning Ball Bearings |
| NSK NSKNU2304ET Bearing | 20 | 52 | 21 | NSK | Cylindrical Roller Bearings |
| SKF N2304 Bearing | 20 | 52 | 21 | SKF | Cylindrical Roller Bearings |
| NSK NUP 2304 E Bearing | 20 | 52 | 21 | NSK | Cylindrical Roller Bearings |
| KOYO NJ 2304 +HJ 2304 Bearing | 20 | 52 | 21 | KOYO | Cylindrical Roller Bearings |
| NACHI 2304 Bearing | 20 | 52 | 21 | NACHI | Self-aligning Ball Bearings |
| SKF *NJ2304ECP Bearing | 20 | 52 | 21 | SKF | Cylindrical Roller Bearings |