Mesee 2 in 1 Digital Angle Finder Protractor Ruler - Combines a ruler and protractor for measuring length and angles; features both metric and imperial units laser-etched on the edge - Equipped with an LCD display for quick and accurate angle calculations; clear digital readout visible even in low light - 360-degree rotation design enables measurement of inside, outside, and reverse angles from 0 to 360 degrees - Features a locking knob to secure the angle at any position; hold button allows instant angle retention - Ideal for DIY home projects, construction, woodworking, measuring, sketching, and drawing - Made from carbon fiber and ABS material - Auto power-off after 5 minutes of inactivity - Battery installation: Slide the latch at the bottom of the LCD screen, remove the battery compartment, insert the battery with negative pole facing up and positive pole down, then reinsert the compartment. Remove battery if not in use for extended periods - Operation: - HOLD button: Press to freeze displayed angle (shown by "H" in upper left); press again to resume measurement - ON/OFF/ZERO button: Press to set reference point (zero) at any angle; press and hold to power on/off - D/M button: Switch between degree and minute display modes - Package includes: 1 x Digital Angle Ruler