Boreas LX is a wristwatch by Martin Braun.

Astronomical watch with automatic winding, which can indicate the sunrise and sunset times as well as the equation of time. For a correct display each watch is individually adjusted to the place specified by the buyer.

On the left side there is a dial indicator for the times of sunrise, on the right for the sunset times. Since it is an astronomical display, daylight saving time is not considered.

In addition, the LX model has an integrated service display, which runs four years. After this time, the indicator dot becomes red and indicates that it is time for a service.

This watch, as usual for Martin Braun, comes in several versions, which distinguish especially through the dial and the housing material.

Overall, the watch is very similar to the EOS, which is also reflected by its name Boreas in Greek mythology is the child of Eos, the goddess of the dawn. The main difference from the EOS is the additional indicator of the equation of time, an astronomical complication, which indicates the difference from the mean local time to true local time.