Greased Lightning was originally made by a small chemical company in Clemson, South Carolina. I used to drive by their plant on my way to work. They sold out to a company in Georgia at least 10 years ago. I am guessing they wanted to get the rights to the name because there are a lot of similar products on the market (Purple Power, Simple Green, etc.). I know the original stuff was really good. It would cut soap scum off a tub in seconds. I have used the stuff from the Georgia company once or twice and although the formula may have changed, it is still pretty effective.
A lot of these cleaning compounds are aqueous mixtures of sodium hydroxide and a solvent such as 2-butoxyethanol. The MSDS for Greased Lightning indicates that its pH is 12.5 to 13. That tells me they use a sodium hydroxide in the formulation, and the MSDS indicates that it is classified as a corrosive liquid.
