Professional reporter: The protractor has passed our rigorous testing to ensure more precise accuracy. The accuracy of the protractor is 0.2 and the measuring range is 0-360. Protractor Folded Length: 200mm/7.9inch, total length: 400mm/15.7in. Two-in-one function: The two-in-one combination of ruler and digital protractor can measure length and angle. It is very suitable for wood processing, architectural decoration, mechanical processing, architectural drawing, home DIY, school teaching utensils. Function of buttons: ON/OFF/ZERO buttons (long press OFF button to power off), data lock HOLD button (after lock, there is no need to worry about data deviation), D/M button . Lightweight and Portable: Compared with stainless steel protractor, this protractor is lighter and safer. The stable locking rotator can lock any angle of the protractor. Large LCD display: The angle ruler is equipped with a large LCD screen, you can easily read the data, and it is very friendly for vulnerable people. If the digital angle ruler is not used for a long time, the angle ruler will automatically shut down to extend battery life.