( JPEG format )A thin flexible lamella, fixed at one end and bent at a right angle at the other, extends into the center of a round metal frame. The player holds this frame with one hand and inserts the narrow part of the frame horizontally into his mouth. A sound is produced by plucking the end of the lamella with a finger, usually the index finger.The oral cavity acts as a resonator and by changing its shape the player can control the resulting overtones.