409B Electrosolve Contact Cleaner is a very fast-drying contact cleaner spray that leaves zero residue. It is effective in dissolving oils and non-polar residues, and in assisting with the removal of oxidation when used with a brush. It cleans connectors, contacts, circuit breakers, microprocessors, and LED and PCB components.ATTENTION! Do NOT use on live circuits. For use on equipment that will not tolerate aqueous cleaning solutions. Not for use in direct contact with food.