- 1). Locate the positive anode (+, longest leg) and negative cathode (-) leg of the LED bulbs. Use your red felt pen to mark the anode and the black pen to mark the cathode.
- 2). Cut open your old battery with a sharp knife. You need to remove the top plastic piece that holds the positive and negative contacts of the battery. Your bulbs attach to this plastic piece.
- 3). Bend the legs of each LED bulb toward each other with pliers, joining them together as one row of bulbs.
- 4). Join red to black in the three LED bulbs by soldering them together. Make sure they are joined closely together. Solder the bulbs as quickly as possible since they do not respond well to high temperatures.
- 5). Cut off the excess legs that extend from the soldering points using wire cutters.
- 6). Place the row of three LED bulbs in the plastic contact piece from Step 2. Adjust the red and black legs so they can be secured to the back of the battery contact part. Trim any excess leg if needed.
- 7). Connect the black leg to the round contact piece and the red to the other one. Solder them together quickly. Adjust the bulbs if needed.
- 8). Place the plastic contact piece that contains the bulbs over the new battery. Place the corresponding anodes and cathodes together on the battery. The flashlight should light up. To turn it off, detach one or both of the contacts (positive or negative).
- 9). Glue the small magnet to the back of the battery if you want to stick it on the refrigerator for easy access.
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