It looks like a square. but closer inspection reveals a hexagonal shape. The all-metal polygonal shape. with its restrained corners. is more solid than poppy. With a small lens diameter. options other than Boston round are rare.
Size:
Width of front: 129mm Height of the front: 40mm Width of lens: 38mm Height of lens: 42mm Bridge width: 21mm Temple length: 129mm *Please allow for slight variations.
