I write it use for few times, because I can give useful review. The device has lower and upper back massage, neck massage and lower Thigh vibration functions. Advantage: if man is very tired; especially after daily office / work table, or working day long because of the lower back hurts, then helps this device. After 10-15 min massage one notices the difference. But after an athletic performance when muscles are exhausted, one should use it immediately. Otherwise you can get hurt. Can you stay 30 minutes and are then let massage.
Disadvantages: 1) The back massage focuses only next spine. But not quite for lateral muscles. 2) trapezius muscles (shoulder) are not served. 3) vibration on seats not mass acts butt muscles. 4) neck function does not apply the correct muscles. So not very helpful.
as I said, if man is really tired, then it helps. But for all the back massage, it is not the right one.