http://www.eagletreesystems.com/sailplane/sailplane.html

We are pleased to offer our Seagull Glide system (patent pending),
a revolutionary Variometer and Soaring Tool for model sailplanes.

With the Glide system, data previously available only on full sized gliders is
provided to the pilot in real-time. Unlike other limited feature variometers on
the market, the Glide system has a fully digital wireless link, data logging,
tremendous expandability, and many other advanced features.