Check the shelf where you buy your 'mineral spirits', usually right next to it is 'paint thinner' read the label of that, if it says 100% mineral spirits, you just saved yourself a few bucks. Now it is slightly different in that 'paint thinner' isn't as refined as true 'mineral spirits', so it can be compared to the difference between 87 octane and 93 octane gas. But for cleaning parts..... paint thinner is my choice.