There are no side effects of using. Suitable for family use.
The principle of a massage stick is to massage through an electric current, and its generation must have a condition that the positive and negative poles of the current must be conductive. The massage stick outputs a unipolar current (one pen tip), so the other polar current is transmitted through the hand to form a reflux with the front end of the massage stick pen tip. So it's normal for the grip to feel a bit numb, it's the working principle of the massage stick, not a quality issue.
Use:
1: Turn on the battery lid, insert the 1.5V AA Battery.
2: Put a gel onto the skin (gel enables good electrical contact). Select one of the heads.
3: Click the start button, screen shows "0", hold the trailing end of the pen, put the probe gently on the skin, then slide slowly.
4: When you find the right points, the pen vibrates strongly.
5: Optional from "0" to "9", you can press "+" or "-" Key to adjust.
6:Please press back "0" when finishing, and it auto turns out 3 seconds later.






