Benu EUPHORIA Collection (Luminous Series)Three models from Euphoria collection have a hypnotizing glow in the dark feature. Ocean Breeze, Love Story, and Scent of Irises glow beautifully, exhibiting various colors in the dark. The effect is created by blending the resin with luminescent material that is completely free of radiation and any potential hazards. Color and duration of glowing vary depending on the model of the pen, exposure time to light, and the intensity of the light source.