A Maglite was chosen due to its high durability, and easy access to the internals. A schrader valve sticks out of the battery cap, which allows the gun to be charged using a standard fitting.
If you have a Presta valve, unscrew the top nut and press in to fully deflate the tube. If you have a Schrader valve, simply press the pin in the valve to release remaining air. Step 3 ...