Used air pumps are refurbished with new flapper valves and rubber diaphragms fitted. Each h pump is then tested to ensure optimum performance is intact. However, used equipment do not carry any warrantee. It can be tested before you leave the store, and if in working order, cannot be returned afterwards.
| Model | 5500 | 6500 | 7500 | 8500 | 9500 |
| Power | 2W | 2.5W | 3W | 3.4W | 4W |
| Flow | 1.3L/min | 2.2L/min | 2.4L/min | 3.5L/min | 4L/min |
| Speed | 2 Step | 2 Step | 2 Step | 3 Step | Variable |
| Voltage | 220v AC | 220v AC | 220v AC | 220v AC | 220v AC |