Machinist Square 3" (95 mm X 75 mm)

A machinist square is the metalworkers equivalent of a woodworkers try square. The square refers to the tools primary use of measuring the accuracy of a right angle (90 degrees): to try a surface is to check its straightness or correspondence to an adjoin surface. A small notch has been added to the inside corner of the square to prevent small particles from accumulating and affecting the square's reading.