Barricade Rust Protection for firearms rapidly drives out moisture from firearm metal pores and adds a transparent protective coating which seals the surface. It's the best way to protect your firearms from rust. Withstands 500 hours in ASTM humidity test and 96 hours in ASTM salt spray test. Barricade Rust Protection for firearms is also an excellent penetrant for loosening rusty or frozen parts. 10 oz. aerosol can.