They probably dipped it in Cosmoline. Good stuff. I bought a bunch of Govt. Surplus measuring tools. Micrometers and the like. All dipped in cosmoline. What a mess getting all those to work.
It does work for decades. I just got a gallon of fluid film, holy crap it is like floor wax. Cant thin it either, had to get a air pressurized sprayer for it and wont spray under 50 PSI!
