The PERTEST (Perpendicularity Test Instrument) is designed for a practical, quick, and direct survey of straightness and squareness discrepancies. It does not require cubes, squares, and tare to operate. The PERTEST is readily available granite machine that works with good precision, stability, and repetition.
The PERTEST has an optional sliding gauge stand on the air bearings that aids in avoiding damage and friction. The gauge is moved upwards and downwards by pushing the button. Furthermore, the test instrument comes with a filtering and control unit for the compressed air.