||In this paper a soft gage is built for checking the tolerances of a cylindrical feature on a plate controlled by three datum reference planes. It is verified that the points of the feature lay within the boundary of a virtual gage, which is represented as the locus of the inner/outer points of a circle for a cylindrical feature (holes and pins) and as the locus of the inner/outer points of two parallel segments for a feature composed by two opposite faces (slots and tabs). We report the algorithms, in part updated from previous papers, and an application to a plate with three datum reference planes and with a hole qualified by a position tolerance. Unlike in the previous work, in this application we consider the tolerance with the MMC modifier. The results obtained are compared and discussed to establish which ones better correspond to the real assembly of the part.