This 3-in-1 (Digital Level, Angle Gauge and Tilt Rate) will help take the guesswork out of setting up those critical bevels on your sharpener (or cuts on your table saw, jointer, bandsaw, or drill press table). Just set the unit on a flat reference surface, press the ZERO button to calibrate the display, then attach it to your handle with the powerful magnets (saw blade, fence, etc.), and precisely adjust to the desired angle. The Angle Cube is CNC machined to a squareness of 0.0005" and uses a U.S. made navigational sensor that is compact, offering 0.2 degree accuracy with a resolution of 0.05 degrees at a range of 90 degrees. The large LCD screen makes it easy to read, while strong magnets hold the unit to any steel or cast iron surface. Uses a 9 volt battery, included.