505A Starrett Mitre Saw Protractor 300mm Direct Reading External & Internal Angles, fantastic tool allows direct reading to mitre scales – No Calculations Required

The Starrett ProSite(R) Mitre Saw Protractor takes error-prone calculations out of the process of mitre 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 scales, the red scale and arrow show the angle for a mitre joint, while the black arrow and scale provide the angle to fit a single workpiece to an angle
The 505A ProSite Mitre Protractor is made from durable, 6mm aluminum with Teflon™ ‘O' ring for smooth and precise operation
This innovative tool saves time and reduces waste, it's ideal for carpenters, plumbers and all building trades, a professional tool for the trade