四谷區防空團関東防空演習記念章

See also https://asiamedals.info/threads/1936-three-city-union-air-defense-maneuvers-yotsuya-ward-air-raid-defense-corps-participation-commemorative-badge.25185/ ; https://asiamedals.info/threads/1936-yotsuya-ward-air-defense-corps-sanko-town-branch-badge.26406/. Size 38 x 20 mm...