1975 - Uranus Solar
Uranus Electronics made battery powered and solar models of their LED watches. In the solar models, the solar cells provided power to supplement the batteries, which needed to be replaced periodically.
This model in a gold tone finish has a one-button activator at the 1 o’clock position and a reassessed setting button at the 3 o’clock position. The face of the case has inscribed, “Uranus Solar – LED Ø” The caseback is inscribed “URANUS U.S.A. 98575”
The other solar model was a calculator model. http://www.ledwatches.net/photo-pages/uranus2.htm
See the listing for the 1971 Solar LED Uranus prototype for more background on the firm.