The Starrett ProSite Protractor takes error-prone calculations out of the process of miter cuts Simply set your saw to the angle that you read - upside down or backwards, the reading is always correct This easy-to-use tool has two laser engraved scales Miter cut scale transfers readings directly to the miter saw for miter joints Single cut scale transfers readings directly to the miter saw Compound Cut Conversion Table is specifically for the compound miter saw Performs as a protractor on the reverse side of the tool Performs as a roof pitch with the tool face down