Custom, Two-window Design, 0.79 " X 0.79 " Display/ Garmin Elevate Wrist Heart Rate Monitor/ Up To 21 Days/51 Days With Solar In Smartwatch Mode/ Smart Notifications/ 10 Atm Water Rating/ Activity Tracking Features/ Health Monitoring/ Running, Cycling, Swimming, Golfing Features/ Dedicated Surfing, Windsurfing And Kiteboarding Activities/ Graphite With Black Band Finish