Bellini Sodium Suphite, anhydrous, 1 kg.

Sodium Sulphite (anhydrous), often called Sodium of Soda, is a developer preservitive, mild silver solvent in fine grain developers and post fixer clearing bath. It is used to protect developer solutions from oxidation and (as hypo clear solution) to wash fixer (sodium thiosulfate) from film and photo-paper emulsions,

The molecular formula is: Na2SO3.