Loop Earplugs is No. 18 on the list of the World’s 50 Most Innovative Companies of 2024. Explore the full list of companies that are reshaping industries and culture.

The World Health Organization warns that a billion people under the age of 36 are at risk of losing their hearing to live music and other activities, but typical foam earplugs make you feel like you’re underwater and muffle the sound of a live concert.

The Belgian-based company Loop Earplugs offers an enticing compromise with its earplugs that filter sound instead of blocking it. The company broke $100 million in sales in 2023 with help from its new Loop Switch model that offers three different settings in one plug.

What makes these earplugs extra notable is that they are designed to be seen, with an eye-catching “loop” that sits in your ear like a piece of jewelry.

Loop cofounder Maarten Bodewes—an avid concertgoer and festival attendee—was inspired by his own ringing ears after a late night and his hesitance to wear traditional “foamies.” He aspired to create earplugs, he says, with “a very different image.” He cites the phenomenon of people wearing Beats’s colorful headphones around their necks. Bodewes wanted Loop users to be similarly proud to show off the product.

Since Loop’s launch in 2016, the company has created earplugs for a range of attenuation levels, from a full-quiet model to a pair that offers mild noise reduction, allowing users to hold a conversation while wearing them. But more models led to new consumer behavior: The company discovered in 2021 that its superfans were swapping their Loops in and out for different scenarios up to 12 times a day.

Two years and 30 prototypes later—in October of 2023—Loop launched the Loop Switch as one earplug to unify them all.

The Switch fits into your ear like a traditional Loop, but by twisting the circular piece that sits atop your ear canal—a brilliant bit of micromechanics that adjusts internal filters by micrometers—you can toggle among three different levels of attenuation to achieve, say, a more dialed-in conversation, a quieter morning commute, or a safer night out at a concert.

“We looked at sliding, pressing a button, and even pulling on something to have that experience,” says Loop senior product engineering manager Robrecht Van Velthoven, explaining the challenge of balancing something like user interface with the mechanics of three acoustic systems. “That’s when we came up with the rotation system, [which] was in line with our iconic Loop design.”

Switch has become Loop’s best-selling product on Shopify and has led to an increase in both recurring customers and the amount they spend on an average order.

The company is tripling its R&D budget in 2024 to support an expansive new road map planned by the company’s new VP of product, Chris Lander, who spent more than a decade working on products and platforms at Amazon. “If we say we want to empower how people hear the world, at a certain point we’re going to step to the electric side,” says Bodewes, hinting at what’s to come.

Explore the full 2024 list of Fast Company’s Most Innovative Companies, 606 organizations that are reshaping industries and culture. We’ve selected the firms making the biggest impact across 58 categories, including advertising, artificial intelligence, design, sustainability, and more.