Made from almost 500 metres of rope, the Vermelha Chair by Brazilian designers Fernando and Humberto Campana is our A-Zdvent calendar's letter V.

The Vermelha Chair was created as a "more free, more gestural and more chaotic" seat design and was the first product by the Campana brothers to gain international success.

"Vermelha was the product that we never expected to go into serial production," Fernando Campana told Dezeen in a video interview in 2008. "Many people laughed at us when we made it."

To form the first versions of the chair, the designers would spend up to a week looping and winding rope around the steel frame to build up the seat, back and arms.

In 1997, one of these early designs was spotted in a magazine by Italian brand Edra's creative director Massimo Morozzi – leading to a long collaboration.

"Massimo was our mentor," said Fernando, speaking to Dezeen following Morozzi's death earlier this year. "He gave us the possibility of making our dreams come true."

"He changed [our career]," added Humberto Campana. "He changed it completely. Maybe we would have disappeared without him."

Edra put the design into production and launched the duo towards international fame.

"We designed it in 1993," said Humberto. "Edra started producing it in 1998. Before that we sold just five pieces. And from that moment we started to be well known."

The seat became one of the first a series of furniture pieces by the brothers made from unconventional materials, including soft toys, plastic tubes and cardboard.

It now features in the collections of some of the world's foremost design museums and was included in a retrospective exhibition of the duo's work at the Vitra Design Museum in 2009.

"The Vermelha Chair today is part of museum collections like MoMA, the Pompidou Centre," said Humberto.

Dezeen is publishing an A to Z of iconic chairs to count down the days until Christmas. Catch up with the list so far »