These industrious street vendors in Porto Alegre use a combination of capoeira and carnival mixed with amusing and colorful banter to hawk their wares. They tease and cajole the crowd into purchasing small tins of muscle linament similar to mentholatum. They mix stories of earlier grave injuries suffered in previous attempts at the main attraction, with  displays of agility. They make it quite clear that they will not be performing this dangerous feat until the crowd makes it worth their while. The tins sell for 1 Real (about 30 cents).
They play the crowd for as long as they can until they sense that people are starting to drift away. Finally they make the dive through multiple rings of steak knives, and 5 upright machetes.