Abstract: A system for checking dimensions of mechanical component parts includes a checking probe (4) which can be programmed from a base unit (11) by means of a wireless radio-frequency link. An interface unit (34) connected to or integrated in the base unit includes control devices with at least an infrared receiver (26, 27) causing the generation of a control signal once coded signals are received. The coded signals can be transmitted by a remote controller (37)—which can be of a universal or dedicated type—or by an emitter (24, 25) adjacent to the receiver. In this second case the transmitted coded signal is adapted to be reflected, for example by an operator's finger, and the pair of emitter and receiver forms an optical switch.