OEM has more parts in it, has bigger transformer, weights more, gives more amps and output voltage is stable. Chinese is cheeper. it is difficult or impossible to tell the difference without opening it (or measure weight).
| Current(A) | Voltage(V) | Weight(g) | |
| OEM | 1 | 5.00 | 37 |
| Chinese | 0.5 | 4.5 | 22 |
