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My stimulator turns off by itself

Sometimes this is because the battery is not making contact with the silver battery tags inside the stimulator. This can happen if the stimulator is dropped. If you can see that the battery tags have over bent, then send the stimulator back to Odstock Medical for repair. It might also be the battery. Make sure you use a good brand (we use Duracell's). If you are using rechargeable batteries then make sure they are charged frequently.