【2in1 UV 365 & 395 ULTRAVIOLET LIGHT】-- Emits 365-370 or 395-400 nanometer wavelength black lights. The 365nm UV flashlight is an invisible light. When irradiated with a substance that does not contain a fluorescent agent or substance, it will show the original color of the goods. On the contrary, the stain is particularly noticeable. The 395nm violet flashlight is a kind of purple light, with higher brightness and farther illumination.