Product details: Product Dimensions: 13 x 13 x 1.6 inches. Shipping Weight: 4.1 pounds. Battery type: 2 AAA batteries (Not included). Featrues: HIGH ACCURACY - 4 sensitive electrodes, step on technology, auto-calibration, high precision sensors measure up to 400 lbs (180kg) in 0.2 lb/0.05kg increments. Provide analysis including Weight, BMI, Body Fat, Water Percentage, Skeletal Muscle Rate, Muscle Mass, Bone Mass, Height, BMR and Age. Security and Safety - 1:1 connection with each user, your data won’t be shared with 3rd parties. Able to store up to 12 users' profiles for you and your family to monitor fitness progress. 2 x AAA batteries included. Two Use: Used alone, the body fat scale automatically identifies the user, records and displays various data. Or combined with phone, once connected, all user data will be synchronized to phone automatically. Step-on Technology - No on or off button, just put both feet on the bluetooth smart scale to get measurements and readings.  2.91×1.4inch highlight LCD display to show health data clearly. Syncs with Fitness APP - Smart Body Scale with easy operation, download fitness APP, connect with Bluetooth on iOS or Android, Support iPhone4s, iPad3, iPadMini or higher version/ Android 4.3 or IOS 7.0 or higher. Email us if any complain. Package included: 1x Scale (Not include the battery)