Underpants which protect men's fertility by shielding them from cell phone radiation have hit the market.
Some experts have previously warned that men who constantly carry their smartphone in their pocket could be affecting their sperm count.
Not all academics agree.
But three French students have created underwear using a special fabric to create a barrier to more than 99 percent of the harmful rays.
Duoo Hopeful boxers have a silver fabric woven inside each pair that acts as an protection against electromagnetic waves.
Men who keep a phone in their trouser pocket could be exposing themselves to radiation which lowers their chance of becoming a father, according to some studies.
Experiments have shown that sperm levels can be affected as much as 47 per cent of the time - although they have not been conclusive.
One of the deign team, Antoine Serouille said they got the idea in school when they saw a study about how electromagnetic waves from smartphones are a danger for men's fertility rates.
He said they first thought about creating a special pocket for a phone, but that just cut out the connectivity, so they switched their focus to protective underwear instead.
Consumers can choose from four different colours, red, blue, grey and green.The brand offers a "precious" package, which for €42 Euros ($62) a pair gives full protection, and a cheaper pair at €24.50 Euros that gives only frontal protection.
The latter are also offered as a €40 Euros twin-pack.
Each pair is designed with cotton, polyester, spandex and the team's secret weapon - silver.
And silver woven into the fabric of the pants, creating a so-called Faraday cage. An electromagnetic radiation that hits the cage is distributed evenly throughout it, which ensures nothing is able to enter inside of the cage.
The team says the materials used in the rest of the boxers have been selected with great care to bring lightness, resistance and breathability.
More than 2,000 pairs have been purchased on the website and Serouille says he wears the boxer shorts every day.Low fertility rates aren't just down to the electrical waves.
They can also be affected by things like pesticides and unhealthy diet. A team at the UK's University of Exeter, conducted a systematic review of the findings from ten studies, including 1,492 samples, with the aim of clarifying the potential influence of mobile phones on fertility. In control groups, 50 to 85 per cent of sperm had normal movement.
The researchers found this proportion fell by an average of eight percentage points when there was exposure to mobile phones. Similar effects were seen for sperm viability, while the effects on sperm concentration were less clear.
However Dr Allan Pacey, from Britain's Sheffield University, who researches sperm is not convinced of the danger. He said the quality of evidence from available studies is poor.