A silent alarm you feel instead of one the whole room hears. A focused vibration at your wrist is strong enough to pull a heavy sleeper out of deep sleep, and quiet enough that the person beside you sleeps straight through it. Up to 40 days of use per 1-hour charge, charged from any standard USB adapter or power bank. A lightweight breathable strap adjusts to fit wrists from 5.5 to 7.5 inches (14-19 cm), and the waterproof construction handles sweat, rain, and handwashing. A bright digital display shows time and date, with simple button controls for multiple silent alarms, a timer, and a stopwatch.