Marathon CL800004BG Atomic Bluetooth Clock System - Black Tempered Glass - Batteries Included SELF SETTING/ADJUSTING: Automatically sets and adjusts time and date by connecting to free companion app installed on iOS or Android device MULTIPLE DISPLAY MODES: Easily choose between multiple display modes from within Marathon Clock System app. MULTIPLE ALARMS: Connect and control 5 separate customizable alarms on up to 5 clocks from within Marathon Clock System app. TEMPERATURE & HUMIDITY: Records temperature and humidity, historical data is conveniently plotted in easy to read graph viewable in app. TIMER: Set countdown timer from app.