In the spaces between these bells hang two metal clappers, small pendulums, on nonconductive threads. Music was produced by singing and by instruments, including flutes, rattles, clappers, and bullroarers. Clappers and concussion sticks appear on Egyptian vases as early as 3000 BC. Usually clappers are wood or bamboo, but some legends say Lan's were jade. Some require the use of small wooden clappers, or "kachi-kachi" during the dance. The Ban, or wooden clappers, produce various styles of tone and melody. Tianjin's style of stand-up also includes the use of rhythmic bamboo clappers, "kuaiban". Lan Caihe rode across the sea upon their musical instrument, the jade clappers. During this, the Dragon King of the Eastern Sea spied and envied the clappers. "Games" by Happy Clappers, and "Feedback" by Vargas Blues Band, were released in 1997.