A fipple is constricted mouthpiece formed by a lip or labium with a slot and a stop which can be cork, wood soft enough to fits into the bamboo or other tubular material. This is a category which includes fipple flutes, duct flutes or tubular-ducted flutes. This category is diverse as fipple flutes are found all over the world, includes the fujara, pincullo, moceños, tabor pipe and tin whistle.
The embouchure is the most critical part of the flute second to the labium and wind way. The quality of sound produced by the labium in which it is directly effected by the usage of correct materials and their respective placement during the construction of the flute.