Perform relative/absolute measurement interchange at any position. Angle and slope reading conversion. There is a built-in magnet on the measuring surface, which can be easily attached to the measured object. It will automatically shut down after 5 minutes. Portable size, easy to use with other measurement tools, and expand the measurement range. Power supply: without battery size:56x56x30mm Material:plastic colour:Black Package Contents: 1 x Digital Protractor Only the above package content, other products are not included. Note: Light shooting 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.