New GPS for windsurfers developed in Belgium http://onandon.be/motion/index.html
Discussion: https://www.seabreeze.com.au/forums/Windsurfing/Gps/Motion-aqua-GPS-from-Belgium-seems-to-be-interesting-or-
The long standing standard Locosys has been plagued by a lack of updates and wristband that self combusts after a short time
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Not a windsurfing specific GPS but it does have a big easy to read countdown timer for you racers.
https://www.ebay.com/p/Garmin-Forerunner-201-Black-GPS-Watch/48471312?iid=292802328324&chn=ps
Alan