The clarinet body is made up of the mouthpiece, barrel, upper joint, pads, keys, ring key, rod, lower joint, and bell. The clarinet has one reed. The reed is made of cane, bamboo or plastic, which varies in thickness. The reed is attached to the mouthpiece with a clamp called a "ligature", which is usually made out of metal. Blowing through the mouthpiece makes the reed vibrate, and therefore makes the noise. The body of the clarinet is a cylindrical tube with holes. The holes are covered by the fingers to make musical notes. There are also buttons pressed by the fingers which allow pads over holes to open or close so all notes of the chromatic scale can be played. The buttons are usually played with the "pinkie" finger. 