... 820-9purity:99%stability:Stable, but air sensitive. Incompatible with strong acids, strong oxidizing agents, water, moisture.melting ... and leather industry.Packing :25kg, 50kg, 1000kg/plastic woven bag. External packing is PP woven bag, Internal packing is PE bag ... are "food additives Sodium metabisulfite" printed on the external packing, with the sign of "Avoid moisture and heaStorage & defence: ...