A potassium permanganate-ammonium persulfate reducer that removes silver metal from the negative in approximate proportion to its existing density. In this respect, the action of Reducer III is like development in reverse. The net effect is that the overall density of the negative is diminished.

The kit contains chemicals to make two stock solutions of 1 liter each. The working solution is prepared just prior to use.

Sodium Metabisulfite is included in the kit for an after rinse.