TENS units and similar medical e-stim devices have an extensive track record of safety when used properly. ErosTek devices use similar waveforms and therefore offer a similar level of safety.
E-stim devices made for erotic use have been marketed for over 15 years with few reports of any problems. The typical power output is less than 0.1 watt (1/10 of a watt = not very much power!) ErosTek power units incorporate many features above and beyond most other products such as internal self tests, isolated outputs, symmetric waveforms and more. The features further enhance the level of safety.
Some people have tried to adapt products never designed for human e-stim in the first place. This is almost always unsafe and people have suffered harm from trying to improvise in this way. When the right equipment is used properly, erotic e-stim has an excellent safety record.
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