Great Material: Carbon fiber + ABS, Measuring Length: 0-200mm; Measure Angle: 360 Degree; Accuracy 0.5. 360 degrees: The angle ruler allows a full range of measurement from 0 to 360 degrees, and is used to measure the length, internal and external angles and chambers of objects. LCD display: The Ruler has a locking knob design, which is convenient to lock the angle at any position to achieve accurate measurement. Easy operation: 3 buttons to achieve all functions: unit transform function, hold data function, reset function. Wide applications: Well used in various fields Angle Ruler, Straight Ruler, and Square Ruler. Fit for woodworking, construction, sketching, drawing, Crown molding, baseboard molding and more. Features: 1. 2-in-1 Electronic Angle Finder Ruler: This angle finder ruler can alculate internal and external angles and measure length quickly and accurately (metric and imperial scale) 2. Convenient locking knob: it helps lock two rulers so that the protractor can be held at any angles by it. 3. Come with CR2032 3V Lithium Battery Power Supply, 5 minutes automatic power-off function, can work more than 2000 hours. How to install in battery? 1. Push in the protrusion at the bottom of the LCD. 2. Pull out the battery box. 3. The negative pole of the battery is facing up and the positive pole is facing down. 4. Push the battery box back. It's recommended to take out the battery if you don't use it for a long time. How to Operate: HOLD Button: "H" will appear on the upper left corner when press, the angle data will be held. To return to measure mode, pls press the HOLD button again. ON/OFF/ZERO Button: Press this button to re-zero at any angle. Press a long time for power off. D/M Button: Conversion between Degree and Minute. Specification: Material: Carbon Fiber + ABS Folded Length: 200mm Overall Length: 21.8cm Measure Angle: 0-360 degrees Resolution: 0.05 degree Accuracy: +/- 0.3 degree Battery: 3V CR2032 Automatically Closed Screen Time: 5 mins Package Included: 1 X Digital Angle Ruler Delivery quantity: 1 piece Product color: black red Product size: 21.8*3.5cm Note: Please allow 1-3cm error for manual measurement!!! Seuais Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store