As we continue to creep into the smartwatch era, we see more efforts from watchmakers to build traditional watches that also contain smart features. Think Frederique Constant’s fitness tracking dress watches. Or Casio’s Bluetooth-connected G-Shocks. Junghans’s radio-controlled Max Bill. Or even Ressence’s insane mechanical E-Crown concept. You can now add Longines to that list.

Longines’s VHP quartz watch was already a fascinating study in quartz watch technology, boasting accuracy to within five seconds a year and a “Gear Position Detection” system that can reset the hands to the correct time after experiencing shock or magnetism. Now the watch features a GMT hand that can be set with your smartphone, but rather than relying on Wi-Fi or Bluetooth — which can be a drain on battery power — the watch detects light flashes from your smartphone’s flash to adjust the time.

Here’s how it works: you use a Longines app on your phone that syncs with your smartphone’s clock when traveling, which then transmits a sequence of flashes that communicates the correct time to your watch via a sensor at the 12 o’clock position. The watch also lets you swap the time between local and home by lightly depressing the crown. The idea is to make setting the correct time quicker and easier than if you had to fumble with the crown, which you can still do if you wish.

As of now, the watch appears to be available in a handful of colors: a blue dial on blue rubber, a white dial on a bracelet, a black dial on black rubber, and a black dial with a black PVD case and bracelet. All colorways will be available in 41mm and 43mm sizes. The watch will start at $1,300 for the 41mm versions, $1,350 for the 43mm versions, and there’s a $400 premium for both sizes to upgrade to PVD. The watch, according to a Longines spokesperson, is set to go on sale this winter.