Drawing dimensions describe intent, while a gauge and a force reading describe what actually came off the line. This contact pair uses a 0.58mm +0.01mm gauge as its reference inspection feature. The gauge gives an inspector a fixed shape at a known size, so the check does not depend on how a caliper is held or where it is placed on a small, springy part. The separation force measurement follows, with 0.25N to 0.8N as the acceptance window. Together, the gauge and the force reading convert tolerance grades on a drawing into a physical result that an inspection station can repeat without a coordinate measuring machine. Separation force is the number that reflects both halves of the pair at once. It is measured as the pin is withdrawn from the bore, so it captures the pin's spring behaviour and the bore's actual size in a single value. That is why a contact pair is normally specified by a force range instead of a single diameter. A designer can draw a nominal 0.68mm pin inside a 0.92mm bore and see a clean fit on paper, but only a separation force reading shows whether the assembly develops the contact pressure the design assumed. The ≤10mΩ contact resistance figure sits downstream of that: it is the electrical consequence of a mechanical fit that is doing its job. This is also why the gauge size, small as it looks on a drawing, carries real design meaning. It anchors the inspection of the socket side, and it lets a receiving inspection team compare incoming parts against the same reference from batch to batch. When a supplier quotes a gauge dimension alongside a separation force window, the two numbers are telling a design engineer that the fit is controlled by measurement rather than by assumption.