Nautical metal clasp / latch for bags, boxes, chests, and heavy straps. Comes in three sizes (dimensions approximate), some include a ring, others do not.
Large : 1.75" x 2.5" Clasp / 1" x 2" Ring
Medium : 1.25" X 2" Clasp / 0.75" x 1.5" Ring
Small : 1" x 1.75" Clasp / 5/8" x 1" Ring