Kodak Rapid Fixer Solution Part A is a rapid fixer designed for use with both black and white film and paper and is suitable for machine, tray, or tank processing. Rapid Fixer is designed as a two-part fixer/hardener solution, and this, Part A, is the fixer chemistry, which can be used with the optional Hardener Part B solution for added emulsion protection when required. This 1.2-gallon bottle of liquid concentrate is designed to make 5 gallons of working solution for film.