| Specification | Unit | CST-3 | CST-3.5 |
| Input supply | Volt AC | 220 | 220 |
| Phase | No | 1 | 1 |
| Rating @ 50% duty cycle | KVA | 3 | 3.5 |
| Maximum available current (short circuit) @15% duty cycle | Amps | 3600 | 3600 |
| Mild steel sheet welding thickness range (min. to max.) | SWG | 56 to 16 | 56 to 16 |
| Mild steel wire welding thickness range (min. to max.) | SWG | 30 to 12 | 30 to 12 |
| Stainless steel sheet welding thickness range (min. to max.) | SWG | 58 to 16 | 58 to 16 |
| Stainless steel wire welding thickness range (min. to max.) | SWG | 26 to 20 | 26 to 20 |
| Brass sheet welding thickness range (min. to max.) | SWG | 58 to 28 | 58 to 28 |
| Brass wire welding thickness range (min. to max.) | SWG | 20 to 14 | 20 to 14 |
| Throat height | mm | 100 | 100 |
| Throat depth | mm | 200 | 200 |
| Electrode gap (max. to min.) | mm | 10-3 | 10-3 |
| Insulation | Class | F | F |
| Dimensions (LxWxH) | mm | 1470x860x1340 | 1470x860x1340 |
| Weight (approx) | Kg | 110 | 110 |