These Sharpie Fine Neon Permanent Markers produce vivid neon colours that can be seen in the daylight and glow under black light. The vivid ink will permanently mark on a variety of surfaces such as paper, plastic, wood, leather and more. The ink is non-toxic and water, smear and fade resistant. These markers have a fine bullet nib. They are a great way to add colour to your work. The ink is bright in the daylight and glows under black light.