Vintage 1970s Faded Black Phase III Straps Jacket

See photos for wear on the buckles, a very cool piece, more like a grey shirt jacket, with adjustable buckles to change the silhouette of jacket. No material tag, but with minimal stretch, likely high cotton composition. Measurements (in inch) Shoulder to Shoulder 20 Pit to Pit 22.5 Body Length 28 Sleeve Length 24