Hi Ants,
Thank you for the question regarding WILDFLOWER's barometer. We use a Speedtech recording electronic barometer that hangs on the main bulkhead. It powers on 4xAAA batteries, which last about 2 years. The unit is about 20 years old, and I doubt is still made. I check it regularly with the nearest airport pressure, and it is ivariably accurate. It also reads temperature and humidity. The Speedtech measures 4″ x 5″ x 3/4″, and weighs 4 oz. It has a pair of switches in the back to select metric or English units; It also has on the face four push-buttons to adjust for altitude and to recall all readings made over the past 24 hours. It once sold for $99. A glance at the display presents a clear picture of pressure trends over the past day. All readings over the past 24 hours are stored, so the display can be turned back an hour at a time to see what has happened.
The only thing bogus about this barometer is it shows a sun, a sun with clouds, or clouds with rain..I've taped over that part of the display as you can see in the below photo.
Before the 2020 SHTP start I checked it's calibration with Oakland Airport.
I have no experience with barometer watches. I could ask Stan Honey if you wish.