This Garmin Sport Watch Runs for 3 Weeks on Solar Power

Instead of a battery, the fēnix 6X Pro Solar sportswatch from Garmin, features a transparent lens that functions as its on-board solar cell. It boasts an estimated 21-day battery life and can maintain full power with just 3-hours of sunlight exposure per day. The 6X also features a larger display and upgraded heart rate monitor, which now works underwater for swimmers plus heat & altitude adjusted V02 max monitoring.