The bracelet has an UV-reagent part, and the main part has UV leds built in. If the bracelet receives a signal, the whole part around the wrist lights up, but if there is no signal, it stays transparent. The model has a simple line, what lights up, but it can be replaced with any pattern. It can be made in different colors, so there is a large place for customization. The part around the wrist is made of a bit harder silicon, so it holds fast, and it is unisize.