High Accuracy: Accurate to the ±0.1° at 0° and 90° and ±0.2° from -1-89°. Measure slope angles 4 x 90˚ (total 360˚) Bright LCD Display: Large bright green LCD provides better visibility, so you can easily read your measurements all day and night, even in the darkest spaces. The display value reverses automatically when the electronic level is upside down 2 Measuring Modes: Press the "hold" button to enter absolute angle mode. The value will hold for easy to read. Press the "REF" button to achieve relative measurement mode 3 Measuring Units: This inclinometer provides three different units of measurement selections: degrees, % grade, and IN/FT. You can change the required units in your measurement Audible Indicator: This level will buzz when the level is getting close to plumb or level, helping to achieve a level and 90 degrees when your eyes can't see the display (This version has no magnetic function), Manufacturer: HANGZHOU GREAT STAR INDUSTRIAL CO.,LTD