| Model | NB 201K | NB 251K |
| Input Power (V) | 220 | 220 |
| Rated Input Current (A) | 27.7 | 28.9 |
| Rated Input Capacity (kVA) | 7.9 | 10.6 |
| Rated Open Circuit Voltage(V) | 56 | 56 |
| Welding Current Adjustment Range(A) | 50-200 | 50-250 |
| Rated Output(A) (40℃) | 60%/35%@200 | 60%/35%@250 |
| Weight(kg) | 30.2 | 30.2 |
| Wire Diameter (mm) | 0.8-1.0 | 0.8-1.0 |
| LxWxH (mm) | 635x350x530 | 635x350x530 |