We’ve all been annoyed by someone taking a loud call in a quiet room, and now a Japanese tech company has unveiled a creative, if somewhat bizarre, solution. The Mutalk is a Bluetooth mouthpiece that “mutes” users who speak into it.

Developed by Shiftall, the Mutalk looks a bit like a VR headset that you wear over your mouth. It works on a principle first described over 160 years ago, called a Helmholtz resonator – essentially, the device is designed to create an air pressure pocket in the inner cavity, which keeps sound frequencies from escaping through the air hole.

See Also:

U.S. Repatriates ancient Greek Sculptures to Italy

In effect, the Mutalk muffles a wearer’s speech by -20 decibels, or as much as -30 decibels for louder noises. According to Shiftall, even people sitting right next to the wearer won’t be able to hear what they’re saying. And yes, the cushion bit that you’ll be spitting into is washable.

Read more: New Atlas