This is a two-stringed monochord, unlike the typical monochord which has only one string. It is a science experiment tool used to experiment with changes in pitch and volume. By plucking the strings stretched across the box-shaped sound box and changing the length, thickness, tension, and amplitude of the strings, the properties of sound can be learned visually and experientially. Width: 67.5 cm, Depth: 11.5 cm Height: 6.8 cm, Weight: 874g