The Pedi handle is rechargeable, so that it will always remain at peak power.
The package instructions for the Pedi don't show a photo of how to charge the unit.
However, it just has a simple magnetic attachment - similar to those of some 'Apple' products.
The smooth 'plug' will latch onto an area on the lower front portion of the handle.
You will then see the yellow indicator light come on when it has attached properly.