Reed aerophones is one of the categories of musical instruments found in the Hornbostel-Sachs system of musical instrument classification. In order to produce sound with these Aerophones the player's breath is directed against a lamella or pair of lamellae which periodically interrupt the airflow and cause the air to be set in motion.
422 Reed aerophones
422.1 Double reed instruments - There are two lamellae which beat against one another.
422.3 Reedpipes with free reeds - The reed vibrates through [at] a closely fitted frame. There must be fingerholes, otherwise the instrument belongs to the free reeds 412.13.