The product is very good, good material, good visibility, efficient operation, it's stable. But it has two design flaws: the grips are the same size as the originals on a Xiaomi 1s, and therefore with the hands they easily cover the lights, they should be longer by a few centimeters. The other issue is that you have to activate it by releasing the grip, either to touch the remote control (which works perfectly) or to touch the outer end (which only leaves the light steady, not flashing). It should have a button on the cuff at thumb height. I have also discovered that it is easier to synchronize the set if you turn on the remote control and then hold down the side button of one fist until it flashes quickly, and then do the same with the other.