Hang on wall or free standing. Displays indoor/outdoor temperature, 12 hour time, perpetual calendar, tendency arrow, forecast icon on changing barometric pressure and indoor humidity. Features: atomic time and date with manual setting, automatically updates for daylight saving time (On/Off Option), time zone setting, time alarm with snooze, 3 languages to choose from: English, French, and Spanish, swiss precision sensor, 1- to 99-percent indoor humidity range, negative 21.8 to 157.8° fahrenheit, 14.1 to 99.8° fahrenheit indoor temperature range, up to 330 transmission range and 433.92 MHz transmission frequency. Clock requires 3 "AA" alkaline batteries. Wireless sensor requires 2 "AA" alkaline batteries.