... :99%min Package: 25kg/ bag Sodium Thiosulphate 99%, pentahydrateSodium thiosulfate (Na2S2O3), also spelled sodium thiosulphate, is a colorless crystalline compound that is more familiar as the pentahydrate ... chemicals, Sodium Thiosulfate is our main item, please contact us, if you take an interest. P&B white big crystals Sodium Thiosulphate(Sodium Hyposulfite),pentahydrate 99% purity