Long Serving Time: these angle measurement tools are made of quality ABS material, not easy to or deform, and safe to use, and the locking device contributes to fixing the angle of the ruler to prevent the ruler from sliding LCD Screen: the protractor angle finder comes with a LCD display of 0.1 resolution, measuring range: 0 to 999.9 degrees, the clear and wear resistant scale are easy to read Reverse Angle Function: the precision angle measuring tool can be adjusted at will from 0-180 degrees to measure the inside and outside angles, by turning the locking knob to lock the protractor at any angle, and the digital angle gauge will become a straight ruler when in the 180 degrees position to meet your different measurement needs What You Receive: including 2 pieces of digital angle finder protractors in the unilateral measurement of 200 mm/ 7.87 inches, each comes with a button battery, which is a combination to Color: black Material: ABS Package Contents: 2 x Digital angle finder protractors Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.