Schaeffer's

Schaeffer Manufacturing Company has been blending specialty oils and lubricants in St. Louis since 1839, making it one of the longest-operating lubricant manufacturers in the country. The company focuses on industrial and automotive lubricants sold primarily through direct sales representatives and independent dealers rather than mass retail — Schaeffer products are familiar to fleet mechanics, machinists, and racing teams but are less visible on hardware store shelves.

Penetro 90 is Schaeffer's flagship penetrating oil, distinguished by an oil-based carrier that doesn't evaporate like solvent-heavy competitors. The formula includes three disclosed corrosion inhibitors and PTFE-based friction reducers, which gives it stronger re-seizure prevention than single-application penetrants.