Photo grade, may be used in any photographic formula. Packed in unbreakable 2 lb. Plastic jar containing a speed cups. Added to FG7 1:15 dilution in a 9% solution produces a fine enough grain on medium and high speed films for practically any degree of enlargement. Adding 10 grams of Edwal Sodium Sulfite per liter to exhausted fixer, helps stabilize for silver recovery.