It does exactly what it is designed to do. It has helped me a lot with its indications to prevent children from getting burned by hot water. After 9 months, only the red LED for hot water turns on, the other two, green and blue, seem to have gone off.

Nice little gadget. The only issue is that it looks quite cheap and had some scratches in some areas. However, it does what it describes without any problem.

It's fun, especially if the shower doesn't have much light. However, it significantly reduces water pressure. So if you don't have high pressure in your network, forget about it.