There are elements of the rater square in this solid anodised aluminium body pocket square. The graduations and numbers are permanent, white on black for easy reading. This triangular layout square is imperial with 1.1/2" long sides graduated in 1/16”s, (that’s roughly 38mm long sides). The base is 1/2" wide giving a good solid register against a workpiece. It has a 1/8" offset on one edge and 1/4" on the other.
The hypotenuse features angle graduations in 10° increments. In use, pivoting the square corner against the edge of the work and aligning the 10° mark with the edge, gives an 80° angle between the perpendicular edge of the square and the work. While fully functional, the protractor portion is not as accurate as that on a standard square. Keep it in your pocket and use it for joint layout of small parts or in cramped areas of a project that require simple cut-off or mitre squares.