As an upgrade to it's predecessors, the new GWM500 add the ability to connect with the radio transmitter in China to update the watchs' time & date in addition to adding an additional 18 cities added to the world time mode, for a total of 48-cities. The watchs' time memo function has been replaced with a countdown timer. Black resin band digital watch with neutral face. Basic Information Case size (L× W× H) 56.8 × 46 × 16.6 mm Weight 67 g Case and bezel material Resin / Stainless steel Band Resin Band Construction Shock Resistant Water resistance 200-meter water resistance Time adjustment Radio-controlled Watch; Multi band 6 Power supply and battery life Tough Solar (Solar powered) Exterior Glass Mineral Glass Watch Features World time World time31 time zones (48 cities + coordinated universal time), city code display, daylight saving on/off Stopwatch 1/100-second stopwatchMeasuring capacity: 23:59'59.99''Measuring modes: Elapsed time, split time, 1st-2nd place times Timer Countdown timerMeasuring unit: 1 secondCountdown range: 24 hoursCountdown start time setting range: 1 minutes to 24 hours (1-minute increments and 1-hour increments) Alarm/hourly time signal Daily alarms5 independent daily alarms (4 one-time alarms and 1 snooze alarm)Hourly time signal Light Electro-luminescent backlight Full auto EL light, afterglow Light color EL:Blue Green Calendar Full auto-calendar (to year 2099) Mute feature Button operation tone on/off Energy saving feature Power Saving (Turns off the display when the watch is left in the dark) Battery display/alert Battery power indicator Run time Approx. battery operating time: 9 months on rechargeable battery (operation period with normal use without exposure to light after full charge) 33 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge) Accuracy Accuracy: ±15 seconds per month (with no signal calibration) Other features 12/24-hour format Regular timekeeping: Hour, minute, second, pm, month, date, day Time adjustment details Time calibration signal receptionAuto receive up to six* times a day (remaining auto receives canceled as soon as one is successful)*5 times a day for the Chinese calibration signalManual receiveThe latest signal reception resultsTime Calibration SignalsStation name: DCF77 (Mainflingen, Germany)Frequency: 77.5 kHzStation name: MSF (Anthorn, England)Frequency: 60.0 kHzStation name: WWVB (Fort Collins, United States)Frequency: 60.0 kHzStation name: JJY (Fukushima, Fukuoka/Saga, Japan)Frequency: 40.0 kHz (Fukushima) / 60.0 kHz (Fukuoka/Saga)Station name: BPC (Shangqiu City, Henan Province, China)Frequency: 68.5 kHz
