Sodium Thiosulfate Na2S2O3 Weight 4 Ounce Volume 4 Fluid Ounce Chemical Formula Na2S2O3 . 5H2O Purity Ultra-Pure 99+% Grade Reagent Grade Consistency Fine Powder CAS Number 7772-98-7 You are purchasing 4 Ounces (by weight) of Sodium Thiosulfate (Pentahydrate) in powdered form . The item ships in a 4 Fluid Ounce Polypropylene bottle. Sodium Thiosulfate; also known as Sodium Hyposulfite / Hyposulphite / Soda of Hypo; has hundreds of uses. FREE EXPEDITED SHIPPING We ship THREE TIMES A DAY, 7-Days a week. Your item is guaranteed to be in the mail the SAME DAY you place your order. Transit time from California is 2-4 days throughout the USA. Our bottles are made of sturdy polypropylene. We shrink-wrap the screw tops and seal the bottles in plastic to ensure a spill-free journey.