Kester AW is a highly active inorganic acid type of flux developed for industrial soldering applications where a flux-cored solder wire is desirable. Rapid soldering can be accomplished on all common metals except aluminum and manganese. AW flux is particularly useful for soldering excessively oxidized metals. Kester AW core flux possesses excellent thermal stability to function under prolonged high temperature conditions as with torch or flame soldering. It is not recommended for electrical or electronic soldering applications due to the corrosive nature of the residue.