"Old Reliable" Naccofix is a general purpose, standard hardening fixer, similar to Kodak's F-5. A Ready-to-use fixer, high capacity and long life. Naccofix hardens the emulsion as it fixes films and papers. The harden emulsion will be well protected against any scratches that may occur during handling or storage. Will not bleach prints from over fixing, as do some concentrated fast fixers.