The body of a modern soprano clarinet is equipped with numerous "tone holes" of which seven (six front, one back) are covered with the fingertips, and the rest are opened or closed using a set of keys. These tone holes let the player produce every note of the chromatic scale. On alto and larger clarinets, and a few soprano clarinets, key-covered holes replace some or all finger holes. The most common system of keys was named the Böhm system by its designer Hyacinthe Klosé in honour of flute designer Theobald Böhm, but it is not the same as the Böhm system used on flutes. The other main system of keys is called the Oehler system and is used mostly in Germany and Austria (see History). The related Albert system is used by some jazz, klezmer, and eastern European folk musicians. The Albert and Oehler systems are both based on the early Mueller system.