Ammonium Polyfluoride, CAS 7664-39-3/1341-49-7, is a blended fluoride that has the formula (NH4)HF2 + HF. Ammonium Polyfluoride is 80% HF Acid and 20% Ammonium BiFluoride. It is used for pickling of steels and others metals and for general surface treatment in the metals industry, as an additive in crude oil drilling, as a polishing additive in the aluminum industry, as a polishing, frosting, and etching additive in the glass, ceramic, and porcelain industries, and as a general cleaning additive for aluminum parts cleaners as well as textile cleaning and industrial laundry souring.