Heavy-duty penetrant for rusted and frozen assemblies. Works quickly to penetrate and loosen rust, tar, grease, dirt, carbon deposits and corrosion from metal parts. Frees frozen nuts, bolts and fittings in all types of assemblies. Level 3* Suggested Applications: Lubricates to free any corroded or seized part. Penetrates rust, scale, paint, varnish, carbon, or gum.