Sudan Black is one of the best methods for developing latent fingerprints on greasy or waxy non-porous surfaces such as glass, metal, milk cartons, interiors of gloves, and candles. Shake solution and pour into processing tray. Immerse evidence into solution until development is complete. The resulting print development is a dark blue/black. Photograph immediately to prevent print degradation. Provided as a 32 oz. premix bottle.