In Asia, there are special competitions where kites have complex designs and are equipped with instruments such as whistles that make musical sounds as the wind blows through them. Although all kites have a similar structure, the variety of shapes is almost endless. The size of the kites also varies greatly-some are so large that several people are needed to control them. Kite-fighting contests are also held,in which competitors use their kites to attack and bring down their opponent's kites or cut their strings.