Creaker L28S Wireless Bluetooth Smart Wristband Fitness Tracker and Sleep Monitor (White) Mini,dedicate design; Weight:100g; Bluetooth version: 4.0 (Effective distance:5m-10m ); Wate resistance (can't wear to swim); lithium battery with charging time of 2 hours; SNS function. The classic buckle design offers you the option to adjust caliber for your best fit;The wave inner side design of ventilation of air and sweat keeps your wrist clean and comfortable. The anti-allergy material gives you a comfortable wearing experience; Record every step,including walk and run. Remember the steps; Accurately records of details of exercise;Gradual,scientific plans for exercise;Fully automatical moniter of sleep; Reports of sleep condition;Vibration reminder. Note: Android APP: Support Andriod device with 4.0 BLE, Andriod system 4.3 and above, please scan the QR code below, download "Lefit" APP to get an better experience, or search "Lefit" in the Google play to get a APP ; IOS APP Support IOS device with 4.0 BLE, IOS 7.0 and above, please scan the QR code below, download "Lefit" APP to get an better experience, or search keyword "Lefit" in the App Store to get the APP.