By Shasta Darlington

Sao Paulo, Brazil (CNN) - They once were worn exclusively by Brazil's working class, but now Havaianas can be found in dozens of countries.

With its growing popularity the flip-flop brand has become one of Brazil's most coveted products both at home and around the world.

They come in brown, blue, pink, and yellow. Slapping up and down the busy streets of Brazilian shantytowns like Paraisopolis. In this town flip-flops are as ubiquitous as the tangled electrical wires and crooked brick shacks.

In fact, this is where Havaianas got their humble start.

Shoemaker Alpargatas says it repositioned its Havaianas brand to broaden its appeal across classes and nationalities.

"We started with the foundation of a good, solid product and then we added emotional attributes, a passion for colors, for the brand for the Brazilian spirit," said President of Alpargatas Marcio Utsch.

Once shoes for maids and nannies, Havaianas now has its showcase store on Sao Paulo's most expensive, most exclusive street.

Stacks of no-frills flip-flops and fancy designs, or design your own shoe. You can spend as little as $12 and as much as $250 for the now world-famous plastic sandals.

Samili has been using them since she was 15-years-old.

"I use them every day, it's so comfortable to get home and put them on," said Samili.

It's hard to think of a beach anywhere without a pair of Havaianas.

Alpargatas raked in $1.4 billion in revenues last year, a figure it wants to more than double by 2015, largely by selling more Havaianas in foreign markets.

Utsch says the "Made in Brazil" label has never been so valuable, with the country preparing to host both the World Cup and the Olympic Games.

"We're taking advantage of this fad, this wave, which I hope turns into a tide that never ends," he said.

They're now testing the waters in China, India, and Pakistan.

But Havaianas is keenly aware of its origins. There's no plan to make the flip-flops anywhere but in Brazil.

CNN