Starrett CP505A-12 ProSite Combination Protractor Miter cut (for miter joints): transfer readings directly to the miter saw Single cut (for butt joints): transfer readings directly to the miter saw Protractor (Reverse side of tool): the actual angle on two scales: 0-180-0 degree and 180-0-180 degree With the tool face down, a quick 5. reference to common roof pitches can be determined by matching the leg of the tool to the lines on the roof pitch scale New upgraded design includes laser engraved dial for exceptional accuracy Precision machined aluminum construction Now performs 5 functions to quickly master your work Saves time and minimizes waste Teflon "O" ring for smooth and precise operation 12-Inch long; 1-1/4-Pound; 1-year warranty