UNIQUE!! Ergonomic Jeans" "SAMPLE"?? Plaid Jacket

This jacket came out of a Philadelphia Vintage clothing store purchased in a lot during liquidation. I'm unfamiliar with the maker "ergonomics jeans" and I have no other info on the jackets origin It does not have any size tag (only what is shown in the pics) . It does say "Sample" on the tag shown. I would say the size is in between a men's medium and a large (it would be a little snug on me) It's super cool though, with a lot of stitching on the breast and red racing stripes down either arm.