Whether you're a light sleeper or a deep dreamer, this Garmin smart sleep band is designed to keep up with your nights. Worn on the upper arm, it's lightweight, breathable, and comfortable, so you can forget it's even there. Along with a nightly sleep score, you'll see sleep stages, heart rate variability (HRV) and total rest time. It's like having a sleep diary that fills itself in. Plus, Pulse Ox technology checks for variations to give you more insight into your overall health.Good to know- Using skin temperature, it helps track menstrual cycles with improved period predictions and past ovulation estimates- No more rude awakenings - a smart alarm gently vibrates to wake you at the optimal time in your sleep cycle- You'll get up to 7 nights on a single charge - that's nearly a full week of sleep tracking without scrambling for a charger- Sync data with your Garmin smartwatch or the Garmin Connect app to get a full picture of your health and fitness__________________Please note: The menstrual cycle tracking feature should not be used in support of conception, contraception or birth control. This is not a medical device and is not intended for use in the diagnosis or monitoring of any medical condition.