Powders are packaged in an easy-to-use aerosol spray container so they may be used on porous or nonporous surfaces. These extremely fine particle powders blend easily on almost any object. The light buff color is almost invisible on a black or white-colored surface. They are highly fluorescent when exposed to longwave (UV) radiation. Simply spray on any surface ”leaving a very fine film, which, when touched, transfers to skin, clothing or other objects. CLUE SPRAY is packaged in a regular 6 oz. (177ml) and pocket-size 4 oz. (118ml) aerosols. Use CLUE SPRAY on carpets, tile, wood and just about any walking surface with limited access for tagging and tracing. In outdoor situations, it may be washed away by rain.