Iron tsuba of square with cut-off edges form (sumi-iri-kakugata) with lattice design in openwork (sukashi) and pierced center.
Unsigned. Late Muromachi period, ca. 16th century.
Size: 73.2 x 72.4 x 3.6 mm
References:
1) Tsuba Kanshoki. Kazutaro Torogoye, 1975, p. 95, lower image. It’s also called Kyō shōami.
2) KTK-11: Koshi motif, Late Muromachi (16th c.)