Krohn Non-Flammable Sparex II Pickling Compound 2.5 lbs. Sparex No 2 is an easy to use longer lasting safe replacement for dangerous sulfuric acid in effective cleaning and pickling metals. A Non-flammable and non-explosive and produces smooth, clean, bright surfaces quickly and economically, without destroying fine detail or tolerances by minimizing the risk of over-pickling, pitting, burning, and wire brushing. The prepared solution has 1½ times the available acid content of a 5% sulfuric acid solution and is more effective than citric acid pickle.