1 dropping bottle of concentrated UV dye. Add to water and most water soluable liquids or gels to create an intense green glow. Glow is so powerfull it is noticable in broad daylight, and under a blacklight it really lights up. Non-toxic, not for internal use. 1 single drop is enough to illuminate half a liter of fluid, with more drops creating an even more intense glow. A great addition to any specimen jars or labware.