100% brand new and high quality.No batteries and external power supply, it will illuminate after water flows downAutomatic light switching.7 colors are displayed automatically when water flowWhen the water temperature below 32 degrees Celsius change into greenWhen the water temperature at 32-38 degrees Celsius displayed as blue.When the water temperature in 39-45 degrees Celsius Displayed redWhen the water temperature exceeds 45 degrees Celsius, red flashing warning, be careful to avoid being scaldedABS material, excellent corrosion resistance, durableTransforming the stream of water into a beautiful waterfall of light.Fits all standard connectors, easy to install.Offer you a delight bath & a wonderful experienceIdeal for bathroom to make it more fantasticGet the CE & RoHS certificatesInternal thread diameter: 20MMSize:Approx 90*113 mm (L*W)Please note: The working principle of the product is hydroelectric generation, which require a larger water pressure to generate electricity. The product need to clean regularly, any impurities or dirt is likely to cause the product will not light. If the product not work, please find a place with larger water pressure to test it, or use your mouth and try your best to blow air into the product. If be jammed with impurities into the interior of the generator impeller and lead to the product not work, please solve it by high pressure air gun. Hope for understandingincludes:1 Colorful shower