This GoWISE USA Body Fat scale measures four components of the body: body fat, water, bone mass, and muscle mass. It is equipped with sensors on a tempered glass platform. This scale uses a measurement method called Bioelectrical Impedance Analysis (BIA). This type of technology uses a minute electrical current and passes it through the body to estimate the measurements of each component. It can store information for 8 users. This Body Fat scale has an Auto-On function, LCD backlight, a touch switch, a weight capacity of 400 lbs., and an athlete mode. Athlete mode uses additional software to calculate accurate results for highly active individuals. It is powered by (2) CR2032 lithium batteries (included).