Stoner Heavy Duty Rust Preventive A677 – Heavy Duty Rust Preventive A677 Heavy Duty Rust Preventive provides long-term protection against moisture and oxidation. It prevents rust and corrosion from ruining exposed steel and stored metals for extended time periods. It allows you to ship or store parts, molds, tooling, or machinery without damage from rust, corrosion, or oxidation. Stoner Heavy Duty Rust Preventive is available through HeatSource.