Bang Good has the Xiaomi Mi Band Bluetooth Fitness and Sleep Tracker in Black for $19.49 (regularly $34.99) with Free Shipping for a limited time.

The Mi Band is a fitness tracking wrist band that monitors your fitness and automatically tracks your sleep. Featuring the industry’s most power-efficient Bluetooth chip and accelerometer, the Mi Band can be powered for up to 30 days on a single charge, and also doubles up as a smart vibration alarm clock and notifies you of incoming calls. It’s compatible with iOS 7 and above or Android 4.4 and above devices.