Vintage Great Lakes Detroit Windbreaker-style Jacket - Size Large

Vintage Great Lakes Detroit Windbreaker-style Jacket. It is in great condition. Dunno its age, but judging by the tag could it be 70s? Seems to be a large, but there is no size tag. See measurements in pictures. It seems to have had a patch over the right chest that is missing. It’s barely noticeable - you have to be inches from it to see the faint stitch line, which will probably go away. Cool retro/vintage item.