I'm one of those label reading guys. Testor's liquid (glass bottle) is MEK. I use Ambroid, which is methylene chloride, also something you don't want to play with. It is the active ingredient in the most powerful paint removers. The Ambroid may not be as strong, but the paint remover will definitely burn your skin, and the vapors are bad news. As the labels say: "Use with adequate ventilation"!