The product has excellent water conservation function, and connected at the top with the water-saving filter.LED emitting color: Green, Red & Blue .Internal diameter: 0.6 inch. External thread diameter: 0.86 inch. Item size: 1.4 * 0.95 * 0.95 inch.The product is externally threaded connector with internally threaded adapter. Adapter can make the product suitable for a variety of faucet interface.When the water temperature is below 32 degrees, the light color is blue. When the water temperature is between 33 to 41 degrees, the right shows green. When the water temperature is between 42 to 45 degrees, it will display the red. When the water temperature is higher than 46 degrees, the light flashing red.This product has mini built-in generating electricity devices, no need of batteries, as long as the water flow it will give out light, turn off the water, the light goes out immediately. The color changes according to the water temperature.