I found your order and see that two of our item # LIT-53LED 53 LED headlights were on it. Those headlights are powered by 3 AA batteries. Each 53 LED headlight requires 3 AA batteries to operate.
We also have headlights that are powered from the battery pack such as our item # LIT-150 3 ultra-bright LED headlight which runs on battery packs between 24 and 72 Volts. It requires a separate switch to turn it on and off and wiring between it, the switch, and the battery pack.
Since you need to be able to transfer the headlights from one power chair to another the LIT-53LED headlights would be the best choice because they have internal batteries and do not require any wiring.
Please let us know if you have any questions.