Mesee 2 in 1 Digital Angle Finder Protractor Ruler - Combines a ruler and protractor for measuring length and angles. Metric and imperial measurements are laser-etched on the edge of the ruler. - Features an LCD display for quick and accurate angle calculation. The digital screen is clear and easy to read, even in low light. - 360-degree design allows measurement of inside, outside, and reverse angles from 0 to 360 degrees. - Equipped with a locking knob to secure the angle at any position. The hold button retains the current reading for convenience. - Ideal for DIY home projects, construction, woodworking, measuring, sketching, and drawing. Specification: Material: Carbon Fiber + ABS Auto power-off time: 5 minutes Battery Installation: 1. Push the protrusion at the bottom of the LCD. 2. Pull out the battery compartment. 3. Insert the battery with the negative pole facing up and the positive pole facing down. 4. Reinsert the battery compartment. Remove the battery if the device will not be used for an extended period. Operation: - HOLD Button: Press to freeze the displayed angle. "H" appears in the upper left corner. Press again to return to measurement mode. - ON/OFF/ZERO Button: Press to set the current angle as zero. Press and hold to turn the device off. - D/M Button: Switch between degree and minute units. Package Includes: 1 x Digital Angle Ruler