This plaque was for the Office of Special Advisors called “Okdang,”and the calligraphy on it was written by Kim Jin-Gyu (1658-1716), the fourth ranking official at the royal office. Okdang (Jade Hall) was another name for the Office of Special Advisors. This office served as an academic institution as well as an advisory board to the king, yet it held the royal authority in check along with Office of Inspector General and Office of Censors.