Ensure that chassis tubing is level and plumb when building roll cages or checking driveshaft angles. Also works on trailing arms and suspension tubes when used with ALL10740 Smart Tool Tray. A "hold" button freezes and unfreezes readings which can be displayed as degrees, percentages, or in./ft. at the push of a button. Plus and minus signs indicate when pitch is more or less than that shown on the display. Pitch reads in 1/8 in./ft. increments. Listen and level emits an audible "beep" at level and plumb. The tool shuts off automatically if idle for more than six minutes. Powered by a standard 9 volt battery.