This tool is used to extract the mass properties of an object. With the tool active, click on the object. The Mass Properties Tool Options palette is displayed with the information about the object's masses. It is organized in 3 parts: Mass Properties displays information about the object's axes. Weight And Volume contains information about the object's density, volume, and weight. Moments Of Inertia contains the respective information. The units of measurement for weight and volume are selected from the popup menus next to the respective fields.