Put your best foot forward with the NuBand Optim smartwatch. Keep track steps, distance and calories, helping you to achieve your day-to-day goals. The dynamic heart rate monitor keeps a finger on your pulse and constantly records your heart rate which you can access, along with all your other activity stats, via the free NuBand app. Not only that, but you can also monitor and track your sleep quality and receive call and media notifications. Throughout your day you can view your progress from the full colour touch screen. Plus, its compatible with Bluetooth, iOS 8.0 and Android 5.0. Model: NU-G0039BK. Size: large. Tracks steps, distance, calories, heart rate and sleep. Call notifications with caller ID, text notifications, email notifications, . Compatible with iOS 8 and Android 5.0 upward. Connects via Bluetooth. 48 hours battery life from a 3 hour charge. 3cm. Size H25.5, W4.5, D1.3cm. Weight 65g.