Starrett CP505A-12 ProSite Combination Protractor
The Starrett ProSite CP505A-12 Combination Protractor is precision machined from lightweight aluminum and features a Teflon "O" ring  for smooth and precise operation.  The scales on this new tool are laser engraved for exceptional accuracy.  As with all 505 series protractors,  the CP505A-12 eliminates the guessing and the math, saving time and minimizing waste.  The 5 great functions provide all you need to quickly master your work:  Miter cuts, single cut, compound cut conversion table for cutting crown molding as it lays flat, protractor 0 - 180 - 0 and 180 - 0 - 180, and a quick reference to common roof pitches.