The TimeCapsule is a candy bar-sized enclosure that replaces an AirTag’s CR2032 coin cell battery with an electrical contact and slots for a pair of AA batteries. It’s made of “fiber reinforced polycarbonate” that won’t block or reduce the range of Bluetooth or UWB signals, according to Elevation Lab’s Casey Hopkins. The case also has an IP69 rating, which offers the highest protection against water, dust, and dirt ingress. No point in a ten-year tracker that can’t handle a puddle.

There are tradeoffs, of course. The TimeCapsule weighs 3.5 ounces with the batteries installed, compared to .39 ounces for a regulation AirTag. And the case does muffle the volume of the AirTag’s chirps by about a third, potentially making it harder to locate by ear. But for situations where you really don’t want to be replacing your AirTag’s battery every year, that seems like a small price to pay.

The company recommends using Energizer Ultimate Lithium AAs to maximize battery life and avoid the leaks and corrosion that alkaline batteries are known for. You can also use nickel–metal hydride batteries, but they won’t quite last as long before needing to be recharged.