This appears to be a 1950s British military jacket. I don't have much knowledge about it, but after researching the internal inspection stamps shown in the images, I've identified it as a 1950 Pattern Khaki Drill Bush Jacket. I'm not an expert on British military items, so please understand that this identification may not be completely accurate. Also, based on how it fits a 165cm, 65kg male, it feels like a size M. If you'd like the measurements, please comment and I will measure it. 1950 Pattern Khaki Drill Bush Jacket #military #50s