【WATER TEMPERATURE CONTROL】 The brightness of the LED lights depends on the water pressure. When the water temperature is lower than 31 ℃, the LED light will show green When the water temperature is between 32 ℃ -43 ℃, it is displayed in blue When the water temperature is between 44 ℃ -50 it, it appears in red When the water temperature exceeds 51, be careful not to burn yourself, the red flashing reminds 【100% SAFETY】 Unique temperature sensor LED light can let you know the current water temperature anytime. And without a battery, the energy comes from the pressure of the water, an energy absolutely sufficient to environment and of excellent quality to ensure sustainability. 【NO BATTERY NEEDED】 Powered by the water flow - No batteries or additional power source needed, the LED shower head is powered by the water flow. Energy saving and respect for the environment. 【EASY TO INSTALL】 Universal connector and easy installation - Connect directly to the shower tube, no other accessories