Structure:shockproofCarbon Core Protection structure Time adjustment:Bluetooth: Connects to smartphone and automatically sets the time Power supply and battery life:Tough Solar (Solar powered) App connection feature:Automatic time adjustmentEasy time settingNearly 300 world time citiesflight logphone finder World time:Dual time (Home City time change) Stopwatch:1-second stopwatch Measuring capacity: 23:59'59. Measurement modes: Elapsed time, split time Timer:Countdown timer Unit of measurement: 1 second Countdown range: 24 hours Countdown start time setting range: 1 minute to 24 hours (1 minute increments and 1 hour increments) Alarm/hourly time signal:daily alarm Light:LED light (Super Illuminator) Afterglow Calendar:Fully automatic calendar (until 2099) Energy saving feature:Power Saving (hands stop to save power when the watch is left in the dark) Battery indicator/warning:Battery level indicator Working time:Approximate battery operating time: 5 months on rechargeable battery (operation time in normal use without exposure to light after charging) 18 months on rechargeable battery (operation time when stored in complete darkness with the power saving function on after a full charge) Precision:Accuracy: ±15 seconds per month (without mobile connection function) Other features:Date displayday indicatorNormal timekeeping: Analog: 3 hands (hour, minute (hand moves every 10 seconds), second), 3 dials (dual time hour and minute, dual time 24 hour, day) Strap Structure:shockproofCarbon Core Protection structure Time adjustment:Bluetooth: Connects to smartphone and automatically sets the time Power supply and battery life:Tough Solar (Solar powered) App connection feature:Automatic time adjustmentEasy time settingNearly 300 world time citiesflight logphone finder World time:Dual time (Home City time change) Stopwatch:1-second stopwatch Measuring capacity: 23:59'59. Measurement modes: Elapsed time, split time Timer:Countdown timer Unit of measurement: 1 second Countdown range: 24 hours Countdown start time setting range: 1 minute to 24 hours (1 minute increments and 1 hour increments) Alarm/hourly time signal:daily alarm Light:LED light (Super Illuminator) Afterglow Calendar:Fully automatic calendar (until 2099) Energy saving feature:Power Saving (hands stop to save power when the watch is left in the dark) Battery indicator/warning:Battery level indicator Working time:Approximate battery operating time: 5 months on rechargeable battery (operation time in normal use without exposure to light after charging) 18 months on rechargeable battery (operation time when stored in complete darkness with the power saving function on after a full charge) Precision:Accuracy: ±15 seconds per month (without mobile connection function) Other features:Date displayday indicatorNormal timekeeping: Analog: 3 hands (hour, minute (hand moves every 10 seconds), second), 3 dials (dual time hour and minute, dual time 24 hour, day)