This bike helmet inflates when you want to wear it—and can fold into your backpack if you don’t

A decade ago, as bike commuting surged in London, three U.K.-based designers started thinking about how to improve safety. What if a helmet could fold flat when it wasn’t in use so a cyclist could easily carry it around? “We knew it was on the edge of impossibility,” says Colin Herperger, an architectural designer who led the project. “But we had a suspicion that it could exist.” 

After years of R&D, their new design, the inflatable Ventete aH-1, hit the market in the U.K. last year and sold out within hours. Later this year, it’s expected to roll out in the U.S. 

The helmet, which retails for £350 (about $450), folds down to a tenth of its size to slide into a backpack. When you’re ready to jump on a bike, a small USB-C pump attaches to a valve and fills the helmet with air. (Any tire pump can also do the job.) Within 30 seconds, it expands, accordion-style, and the ballistic fabric becomes rigid and strong. In a safety study at Imperial College London, the design outperformed 30 conventional competitors in tests of linear impact absorption. 

As the designers expected, the development was challenging. The team initially experimented with 3D printing, then pivoted to fabric, partnering with other companies to create custom materials that could meet their complex performance requirements. Because nothing like this had been produced before, the process also involved innovative manufacturing techniques, such as creating new tools for high-frequency welding. 

The startup went through more than 100 iterations before getting to the design that came to market; the company now holds 26 patents. The final helmet has other advantages beyond its portability and strength. Unlike a foam helmet, it doesn’t hold in heat, so it’s more comfortable to wear. And while foam helmets become less effective if they’re dropped, the Ventete helmet’s pressurized air makes the new version more resilient. It arguably also looks better than a typical helmet—making it more likely that riders will actually want to wear it. 

Explore the full list of Fast Company’s World Changing Ideas, 100 inspiring projects that are making the world more accessible, equitable, and sustainable for everyone.