• 1
    3D-print the base of the ring

    The STL file can be found in the files section. The ring size is 8, so it may not fit everyone's pointer finger.

  • 2
    Insert the battery

    Wire the "+" and "-" terminals out. It's recommended to use 30-32AWG enameled copper wire.

    In the picture above and all remaining instructional pictures, the red wire signals power or "+".

  • 3
    Install the slide switch

    Connect the red wire (the battery's "+") to one end of the switch and solder another wire to the other end.