led world 3W 365nm UV LED Ultraviolet LED Chip Light High Power LED Bead with 20mm Base for DIY Emitting Colour: UV Wave Length: 365nm - 370nm Quantity: 1 Piece DC Forward Voltage: 3.4V - 3.8V DC Forward Current: 700mA Luminous Intensity: 50~55mW Viewing Angle: 120 Degree about the wavelength of 365 LED , Eyes can only see a little bit of purple light . It is different from 400nm uv led light . 400nm uv LED light closer to blue light ,So it looks brighter than 365 nm led light. But in fact the light intensity for 365nm uv light is higher than 400nm uv light , for instance, 365 nm UV curing glue curing speed is the fastest