Full Auto EL Backlight: Automatically deactivates the Auto EL backlight function when surrounding light is sufficient, and activates it under dim light or dark conditions. Solar Power: A solar cell provides power for operation. Compass: A built-in direction sensor detecs magnetic north. Altitude Measurement: A built-in pressure sensor measures barometric pressure, which is converted to relative altitude. Barometic Pressure Measurement: A built-in pressure sensor measures barometric pressure, which is shown on the display. Duplex LCD: Two liquid crystal panels make it possible to select from among different display patterns. Stopwatch: Accurate measurement of elapsed time with the touch of a button. Yacht Timer: The yacht timer is used to time the start of regattas. The countdown period can be set from 1 to 10 minutes. An accustic signal is ermitted after each minute has elaapsed and then once a second for the last ten seconds. Daily Alarm, Hourly Time Signal: The daily alarm sounds each day at the time you set. The value indicates how many daily alarms are available. The hourly time signal causes the watch to beep every hour on the hour. Battery Level Indicator: Indicator shows the current battery level. Low-Temperature Resistant: The timekeeping module is designed for operation at very low temperatures. The value indicates the lowest temperature at which the module will operate. *-10 C resistance does not apply to the direction sensor. Full Auto Calendar: Allowances are made automatically for months of different lengths, in case date corrections for leap years are required. 12/24-hour Timekeeping: Times can be displayed in either a 12-hour or 24-hour format. Mineral Glass Hard glass resists scratching. Black rubber strap. Water Resistant: 50 meters, 150 feet.