A round, flat-bodied, four-stringed instrument with a long, straight neck having fourteen frets. Held on the lap, it was plucked with a plectrum. A leather patch at the center of the body serves as a plectrum guard to avoid denting the wood. The plectrum guards for both of the two genkan in the Shōsō-in are beautifully painted with Chinese-style scenes. The two circles above the plectrum guard are decorative rather than encasing holes to release the sound. The genkan is said to be named after a third- or fourth-century Chinese sage who was fond of the instrument.