Date:    Wed, 09 Sep 1998 04:03:00 GMT

There have been many opinions posted here on WD-40's composition, but
here is what the Material Safety Data Sheet [MSDS] says (it's from Oct
93, the latest I could find):

50%   Stoddard solvent (mineral spirits) [8052-41-3]
25%   Liquified petroleum gas (presumably as a propellant)
[68476-85-7]
15+%  Mineral Oil (light lubricating oil) [64742-65-0]
10-%   Inert ingredients

(The numbers in square brackets '[]' are the CAS numbers for the
ingredients, as  listed in the MSDS.)   

Mostly, WD-40 is a solvent, with a bit of light oil mixed in.   It
doesn't contain wax (except incidentally, since it's not exactly a
reagent-grade product).   

Personally, I use it sometimes for small cleaning jobs, but it's not a
particularly good lubricant for anything that I can think of, offhand.

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