Apparently, people might have used it for electrical parts of the system and it must have failed to a significant enough extent for them to bother publishing that on their data sheet.Noticed that the 3M is no longer available on Amazon. Their site says it is an industrial product and not intended for consumer sale or use. I have a jar that is a few years old. It is about half full but starting to solidify. Considering the Raybestos or Mission.