These are hand-stitched butterfly chairs with rustic aged patina leather sling seats and metal frames—a classic mid-century modern design originally popularized by Jorge Ferrari-Hardoy in 1938 (often referred to as the "Hardoy Chair" or "BKF Chair").
Very desirable in vintage and bohemian-style decor! leather is easily removable and they stack!
The seating was folded up before I took the pics, but they will smooth out after a few hours.