This is a SEIKO pocket watch. It's a hand-wound mechanical watch, likely from the 1960s. It's the same model used by the Japanese National Railways. It's still running, and I measured the error over 24 hours, which was only about 2-3 seconds. Considering its age, I think this is acceptable. There are some scratches on the back and a small dent that doesn't show up in the photos, but it looks like it could be polished out. Other than that, it's in good condition with no dirt or damage.