Item Type: Angle Gauge_x000D_ Material: ABS_x000D_ Measuring Range: 4x90_x000D_ Resolution: 0.05_x000D_ Accuracy: 0.2_x000D_ Battery: 2 x AAA Batteries (Battery Not Included)_x000D_ Working Temperature: -10 - 50_x000D_ _x000D_ How to Use:_x000D_ ON/OFF for turn on or off, short press the HOLD / TILT% button, the display will keep the reading data. Long press the HOLD/TILT% button for 2 seconds, the display will change to tilt%. ZERO clear_x000D_ _x000D_ ZERO description:_x000D_ 1. The measurement initially displays 0.00 on the LCD. When it displays "A" on the left "V" on the right, it means that the left is higher and the right is lower; when it displays V" on the left, ""On the right, it means lower on the left and higher on the right._x000D_ 2. Turn on the instrument and start measuring, and read out the relative angle that is absolute horizontal._x000D_ 3. Press the "Zero" button to reset the value for relative measurement.