Attentions:  Message feature only work with Android phones. and you must download an app for it to work. The app can be downloaded through the after sale center of our site: https://www.mediafire.com/?td1b8rr6d0j9xan.<br />It is also the best gift for your family and friends.<br /><br />Screen: OLED capacitive touchscreen display <br />Pedometer: 3D gravity sensor gyro <br />Memory: 32M <br />Speaker: 0.9W<br />Microphone: 38DB flat vibration motor: 8 x 2.7 mm <br />Bluetooth: version 3.0 <br />Battery capacity: 250mAh <br />Charge time: 2-3 hours <br />Standby time: 168 hours <br />Charging DC: 5V / 1A (Please check the charger when charging specification) <br />Charging interface: Universal standard for micro USB<br />Product Weight: 0.04 kg <br />Product Size: 7.3 x 6.0 x 2.9 cm / 2.9 x 2.4 x 1.1 inches<br />Thickness: 1.2 cm / 0.5 inch <br />Diameter: 2.9 cm / 1.1 inch <br />Inner perimeter: About 18.0 cm / 7.1 inch <br /><br />What's in the box?<br />1 x Smart bracelet<br />1 x Micro USB charging cable<br />1 x Manual in English/ Chinese<br />1 x Artist display base