This blackening chemical is used by gunsmiths and industry to blacken aluminum parts. Used at room temperature, it restores scratched and marred areas quickly. Fast-acting liquid is easy to apply with no dimensional change. Color will vary from deep gray to black depending on alloy. Aluminum Black Metal Finish is also excellent for blackening name plates, plaques, trophies and other engraved items. Made in the U.S.A. by Birchwood Casey.