To start you will need a sharp razor blade knife (please use discretion while using sharp objects suck as razor blades). Next take the knife and make a cut big enough to get the small circuit board out.(see photos 2 and 3 for reference).
Step 2: Replace the batteries
Be very careful when taking out the circuit it is very fragile and tiny. Now that you have the circut use a small flat screwdriver to push out the dead batteries. Then look at them close to see what type they are. Then go but those type if you don't already have them. them insert the new batteries.(see photos 1, 2, and 3 for reference).
Step 3: Putting it back together
Now that every thing is done make sure to test the board and see if it works, if so then carefully put the circuit back in the rubber casing. then you can either leave it how it is or seal it up with a small aont of hot glue on the inside so you don't taste it while wearing them.
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