I do really like this product. It vibrates when your posture is not ok.
This is a class of shoulder braces with straps, which go around your shoulders and pull them back. You can record your correct posture. Smart electronic sensors detect the exact tension on the straps. When you slouch, this tension increases. When it increases over certain level, the device will vibrate – warning you that you are hunching your back. When I ordered this posture corrector I was really skeptical about it. But then I was quite surprised how good it is. And easy to use. Would recommend to others.