From the Manufacturer
This Stanley 20-600 Clamping Mitre Box has a 14-inch back saw and a built-in measuring scale. Honeycomb base and cam pins secure work for accurate cuts. Cuts miters on 45-degree and 90-degree, face angle 45-degree, and all new 22-1/2-degree angles (for octagonal shapes) popularly used on architectural details such as bay windows. Molded-in storage compartments to hold cam pins and pencil. Base and pins are molded of high impact resistant material for long life. Comes with miter box and two cam pins. Molded lip on base edge for easy use without mounting. Two screw holes on each side to secure base to work top. Built in saw stop to prevent cutting into miter box. Patented design.