Blak-Ray® Fluorescent Inks are suited for use on skin, fabric, and similar porous or textured surfaces. All inks are formulated to fluoresce brightly under UVP's longwave ultraviolet lamps. These simple to use inks come ready made and won't gum up, so stamp pads stay cleaner longer. Economical - small amounts of ink are used with stamp pads. Readmittance type inks are designed for use at amusement parks, social gatherings and sporting events. Inks are non-toxic, fast-drying and non-transferable.