Basic Yellow 40 is a yellow dye used with a forensic light source or UV lamp after cyanoacrylate development of latent prints. Basic Yellow fluoresces well between 365 and 485 nanometer. A fluorescent dye-stain used to enhance cyanoacrylate-developed latent prints. A forensic light source or ultra-violet lamp that will output light between 365 nm and 500 nm is required for this process. 25 gm A-26501 Chemical Shelf Life: 6 months Working Solution Shelf Life: 6 months