Formulary's Fixer 24 is excellent for use with PMK and other Pyro Film Developers. Fixer 24 is non-hardening sodium thiosulfate fixer. Without hardener, prints are easier to wash, tone, and spot. Prints are fixed in two successive fixing baths requiring 3 to 5 minutes in each bath. The chemicals in this kit are used to make a working solution which has a shelf life of 2 to 4 months. One liter fixes about 25 8x10" prints.