Formulary's Reducer IV For Negatives is similar to Ansco 311. It is not a true reducer, rather it is only a bleach. The chemicals in this kit are used to convert the silver metal in the negative back to a silver halide which then can be reconverted to silver metal in a redevelopment step. Any standard developer can be used for the redevelopment. The chemicals in this kit are used to prepare 1 liter of working solution, which is reusable. The working solution keeps well and has a high capacity.