This product suits the diameter of 23.5 mm tap interface,
1. When the water temperature below 25 degrees, green one year warranty2. When the water temperature at 25 degrees -35 degrees, It shows blue 3. When the water temperature at 35 degrees -45 degrees, It shows red 4. When the water temperature over 45 degrees, to be careful to avoid being burned, oh, flashing red alert you to take care