• It is a solar-powered watch that uses Citizen's Eco-Drive technology. This means it converts any light, natural or artificial, into energy to recharge the battery. So it never needs a traditional battery replacement.

• The Satellite Wave model has the added ability to sync its time globally using signals from GPS satellites. There is a small antenna under the dial that receives satellite signals.

• When in range of GPS signals, the watch syncs to the atomic clock time signal from satellites orbiting the Earth. This keeps the time accurate anywhere in the world and automatically adjusts for daylight savings time.

• Syncing can happen automatically when the watch is exposed to bright light. There is also a button on the case you can push to manually trigger a time sync if needed.

• Between syncs, the Eco-Drive technology keeps the watch powered and keeping accurate quartz time. The power reserve when fully charged is about 6 months

Very cool!