Vessels with twin fish designs were often used as brush washers. The twin fish symbolizes marital happiness. This brush washer has a pair of moulded fish applied on the interior bottom and slender lotus petals carved in relief on the exterior sides. The broad-rimmed vessel curves to a taper at the foot. The crackled glaze is of an unusual vivid sea green colour. Twin fish vessels were made in large quantities at the Longquan kilns during the Southern Song and early Yuan dynasties, and exported to Southeast Asia and the Middle East.