The three men in black t-shirts sweat as profusely as Chris Froome or Peter Sagan at a summit finish, but their toil is unlikely to win them global fame.

Still, much of the world will see the crystal trophies these glassmakers are creating when the Tour de France champion, best youth, best climber and points leader thrust them high into the air on the Champs Elysees on July 24.

A spiral motif adorns the tall, slender trophies designed by Slovak-born Peter Olah for the 103rd edition of the world's toughest cycling race that began July 2.

Their angular hourglass shape is symbolic, says the 38-year-old designer for German-owned Czech car maker Skoda Auto, which has partnered the race for 13 years.

"The bottom is broad just like the start list, then you discover the few favourites symbolised by the slender central part, and the top of the trophy, that's the sole winner," Olah says.

Ultimately, the design must impress when the victor holds it high over head, Olah adds, revealing that the sharp lines of the 60-centimetre (two foot), four-kilo (eight-pound) works of art evoke the design of Skoda cars.

It took the Lasvit glass designer three days to create the trophies at its Ajeto glassworks in northern Czech Republic.

Glassmakers first blow an oval bubble which is then shaped before spending the night in a cooling tunnel. Finishing touches take two days.

- Full circle -

Skoda became the Tour's official partner in 2004 and its cars have since been impossible to miss among the world's top riders during the race.

"We provide a fleet of 250 cars which travel around 2.8 million kilometres every year," says company spokesman Tomas Kubik.

Standing out of the pack is the so-called Red Car, a Skoda Superb with a custom-made sunroof and a cutting-edge communications system for race director Christian Prudhomme.

Also sponsoring ice-hockey and motor sport, the auto manufacturer has come full circle with its Tour sponsorship as the first product made by its founders Vaclav Laurin and Vaclav Klement in 1895 was a bicycle.

Owned by Germany's Volkswagen, Skoda Auto sold more than a million cars worldwide in 2015 despite its parent company's emissions scandal.

Skoda, South Korea's Hyundai and TPCA, a joint venture of Japan's Toyota and France's PSA Peugeot Citroen, drive the economy of the Czech Republic, an EU member of 10.5 million people.

Maker of the world-famous Bohemian crystal, the Czech glass industry is no longer what it used to be as many manufacturers shut down after the 1989 demise of the command-economy Communist regime in former Czechoslovakia.

But the survivors are successful, and Lasvit is one of them.

"We develop and produce unique glass installations for hotels, palaces, residential projects," says Ales Styblo, vice-president for marketing and sales.

Founded in 2007, the company has 45 dealers worldwide and 13 branches in places as remote as Dubai, Hong Kong or the United States.

- Green Peter -

Lasvit and Olah are keen to experiment with different glass-making techniques.

"For the 100th anniversary of the Tour, we used double-layered glass, that is, crystal glass coated with opal glass which was then engraved and polished," says Olah.

The circular section of the trophy was inspired by spinning wheels, just like the handmade spiral that rolls up its outside.

"The glassmakers said this was one of the toughest trophies to create," Olah said.

Last year, Skoda Auto became the official partner of the Tour's green jersey for the points leader, who therefore gets a special trophy made of green glass.

For Olah, who points out the link between the green jersey and the green winged arrow in the car maker's logo, this is something very special.

"I am Slovak so I'm obviously a Peter Sagan fan," he beamed.

"He already has four trophies that I've designed and I hope he'll win another one this year. Fingers crossed!"