NAPA, Perfect Circle, Melling, Sealed Power, and several others sell about the same stuff- - - -looks like red-colored thick motor oil with some sort of sticky additive. I used to use STP as assembly lube, but every engine I built with the stuff seemed to have oil-related problems. I even built one more engine just convince myself it was a fluke- - - -and that one spun a rod bearing!
Jerry