Your fitness has never been easier to stay on top of now with the Letsfit IW1BLACK 1.4" Waterproof IP68 Bluetooth Fitness Smartwatch With Heart Rate Monitor - Black. With features such as SpO2 blood oxygen measuring and an all-new dedicated in-house fitness data app, you'll be able to get more insight into your health and improve your fitness day by day, one step at a time. This smartwatch features automatic sleep tracking that helps you see how you are sleeping to help you change sleeping habits, SpO2 measuring (blood oxygen saturation) for deeper insights into your health, heart rate monitor, and route map with smartphone GPS which provides accurate workout tracking. Works with Letsfit App gives you easy access to everything your smartwatch has to offer. Check all your data in the app, including your fitness metrics, sleep analysis, and more. Get calls and message notifications right from your wrist. Set alarms via Letsfit App and your smartwatch will take you up at the time you've set. The long-lasting battery lasts up to 7 days on a full charge, so you will never run out of battery. This smartwatch is IP68 waterproof, which allows you to go on a wild workout in the rain, sweat to your heart's desire. It doesn't matter what you do, even if your watch gets submerged in water, this smartwatch is protected at all times thanks to a waterproof nano-coating that stops water and keeps your device in top shape at all times.