Chlorine Dioxide For the on demand generation. All in one kit. Set contains 2 solutions 4 fluid ounces Sodium Chlorite Solution (NaClO2) 25% with 4 fl oz ACS grade Hydrochloric Acid (HCl) 4-5%. Store with caps use droppers when dispensing for accurate measurements. Equal drops of Part A with Equal drops Part B. In 2010 ,the FDA issued a warning against improper use not with label and instructions. This product is a chemical solution shipping restrictions to PO Box.