Proster Angle Finder 0-225° Digital Protractor with Battery and Pouch 400mm/16 inch Angle Ruler with Spirit Levels and Backlit LCD Digital Angle Measuring Tool for Roofing EngineeringAngle Finder Protractor This Protractor Can Quickly Measure the Angle Data. With Horizontal and Vertical Bubble, Help You to Judge Horizontal Vertical or Not (Note: NOT a Digital Level, Data of Digital Level are not Displayed on the LCD Display.) Accurate Angle Range is 0 225, Measuring precision: 0. 5, Increase Decrease Angle: 0. 1 Mechanical Lock Knob and Data Hold With Lock Knob, Help You to Keep the Angle Constant when Scribing or Measuring