Glad I decided to to a detail slide strip while cleaning the pistols today. I noticed my new Glock 30S had the extractor spring installed backwards. I doubt it came from Glock that way. Probably someone messing with it before I bought it. It ran fine but I'm glad I caught it early on. It matters because one end is polymer and the other is metal. The polymer should touch the polymer slide cover plate and the metal end should touch the metal extractor. Check your firearms people!