Fitbit Inspire 3 Health &-Fitness-Tracker with Stress Management, Workout Intensity, Sleep Tracking, 24/7 Heart Rate and more, Midnight Zen/Black One Size (S & L Bands Included) Used only once by my dad * Inspire 3 is the tracker that helps you find your energy, do what you love and feel your best. All you have to do is wear it.Operating temperature: 0° to 40°C * Move more: Daily Readiness Score(1), Active Zone Minutes, all-day activity tracking and 24/7 heart rate, 20+ exercise modes, automatic exercise tracking and reminders to move * Stress less: always-on wellness tracking, daily Stress Management Score, mindfulness sessions, relax breathing sessions, irregular heart rhythm notifications(2), SpO2(3), menstrual health tracking, resting heart rate and high/low heart rate notifications * Sleep better: automatic sleep tracking, personalized Sleep Profile(1), daily detailed Sleep Score, smart wake vibrating alarm, sleep mode * Comfortably connected day and night: calls, texts & smartphone app notifications(4), color touchscreen with customizable clock faces, super lightweight and water resistant to 50 meters, up to 10 day battery life(5)