Google is the first major tech company to build the Babel fish.

The search company, which is now making a slew of its own hardware products, announced the Google Pixel Buds at a San Francisco event today (Oct. 4). The earbuds connect wirelessly with Google’s latest smartphones, but more importantly, they’re able to access Google Assistant, the company’s virtual personal concierge, which launched exactly a year ago. Through this software, Google claims the earbuds can translate 40 spoken languages nearly in real time—or at least, fast enough to hold a conversation.

A demonstration on stage during Google’s event showed accurate and nearly instantaneous translation from Swedish to English, but it’s unclear how well it will perform in the real world, where background noise, differences in accent, verbal stumbles, and so on could confuse the software.

Google has been ramping up its translation services for years. Late last year it released a new version of its simultaneous translation service powered completely by artificial intelligence. Quartz tested the service after it launched, and concluded it had some work to do on its Chinese.

The translation itself is currently processed on Google’s AI-focused data-centers, because it takes a lot of processing power. Audio must be converted to text, translated into another language, and then turned back into speech and spoken to the listener.

The last part of that process is traditionally done by putting together pre-recorded words or word fragments. However, DeepMind, Alphabet’s AI research lab, wrote in a blog post today that the AI research it used to generate human-sounding voices—a system called WaveNet—is now in Google Assistant. That means the voice speaking the translations will be generated in real time and thus more realistic, according to DeepMind. What’s unclear is how much of this processing will be done in the cloud and how much on the processor of the phone connected to the new earbuds.

The Google Pixel Buds cost $159 and provide 5 hours of battery life, and can be recharged from a battery pack in their carrying case.