Photo-Flo is a concentrated wetting agent used as a final step in processing to inhibit the formation of water spots or streaks on Films and plates. It is generally used on silver-based black-and-white Films and plates. Photo-Flo can also be used as a surfactant to aid in the smooth application of water-based retouching materials to processed Films, plates and papers, both black-and-white and color. Recommended for use in water only. Not intended to be added to processing solutions.