Heuksamo is one of coronet worn with the civil and military officials' robes for working. Heuksamo is made of black Mora(silk), and two single layered wings are attached horizontally in the rear—this indicates the wearer was the 4th to 9th rank government officials. Gyupsamo is a similar coronet, made with same material, however it has two double layered wings attached horizontally in the rear; this was worn by 1st to 3rd rank government officials.