The surface of this sun dial is flat and it is used in a horizontal position. A large circle is incised on the plate and a triangular gnomon attached upright. The shadow cast on the hour marks along the arc of the large circle tells the time.

There is an inscription in the right-hand corner that this sundial was made in the early part of the 6th lunar month in 1881 by Gang Yun, an important sundial maker of the late Joseon period. The inscription on the left-hand corner reads, “the master of Hongyeop-ru (Red-leaf Pavilion) experimentally produced it for Chuiseog-ong (elderly man of jade)” (紅葉少主人爲翠石翁試製). The script at the bottom edge of the plate indicates the standard latitude of Hanyang – the capital of Joseon and present-day Seoul – 37º 39’ 15”.