4 & 1 Hypo Eliminator is a liquid concentrate that reduces washing time and is the hypo eliminator that removes (1) hypo, (2) excess silver ions, (3) silver hypo complexes, (4) polythionates and at the same time coats film, making it more resistant to atmospheric pollutant. That's "4 & 1".
Highly recommended not only for standard prints and film, but for the finest quality archival processing, producing true archival permanence. Simply stated, Edwal 4 & 1 means purity — 4 ways and 1 unique method of protection.
