Evapo-Rust 1595750 (1 gallon) is ready to use—no mixing or dilution required. Remove excess dirt, grease, and oil from the rusty item. Pour Evapo-Rust into a container and fully submerge the item. Soak for about 30 minutes for light rust, or overnight for heavy rust. Rinse thoroughly with water and allow the item to dry. Tip: You can reuse the solution until it loses effectiveness. Do not use it on magnesium or magnesium alloys.