Formulary's Amidol Paper Developer is similar to Ansco 113 and is an alkaline-based amidol developer. The prints resulting from Formulary Amidol Paper Developer are very similar to those obtained using Weston's Amidol Paper Developer - cold tones and deep blacks. If you have used and like the results of Weston's Amidol, you should try this formula. Formulary Amidol developer works best with bromide papers. This developer can be used with or without dilution. Without dilution the prints have high contrast and with dilution the contrast is diminished. The shelf life of the stock solution is six months; after the Amidol is added the shelf life is only 2-3 hours. This kit contains several small packets of Amidol so that you can mix small volumes of working solution.