400mm/16inches Portable 0~225 Degree Professional Protractor Electronic Laser Spirit Level Digital LCD Display Angle Meter

Easily readable LCD display shows the exact angle at once. Automatically shut off after five minutes to prolong the batteries' life. Backlight design: keep its normal use on dark light. Data holding function: Help the use on dark light. Mechanical lock(Lock knob): Keep the angle invariable in the process of line or measure the angle. Low power alarm, notify you the power in advance.