"The vuvuzela is a typical 65 cm (2 ft) plastic blowing horn that produces a loud, distinctive monotone B♭3 note. The vuvuzela is most used at soccer matches in South Africa, and it has become a symbol of South African soccer as the stadiums are filled with its loud and raucous sound that reflects the exhilaration of supporters," informs Wikipedia.
Unfortunately, if you click on the vuvuzela button, you might not be able to hear the original sound of the video. YouTube has an option that provides automatic captions for videos, but the results are rarely accurate.
{ Thanks, Sterling. }