The gWind Wireless' internal batteries are continuously charged by a small solar panel integrated into the transducer arm, and have a lifespan of 3 to 4 years. When they need replacement in due course, you can easily replace them with this NiMH battery.
GNX™ Wireless Sail Package 43
GNX™ Wireless wind package
GNX™ Wireless Sailing Package 52
gWind™ Wireless Transducer
gWind™ Wireless Transducer Bundles
gWind™ Wireless 2 transducer