本图旨在确定螺柱保持间隙直径，以接受标准公制螺柱。这完全基于国际标准化组织（I.S.O.）提出的建议。ISO建议R273，公制螺栓的间隙孔（精细系列）和R286，ISO极限和配合系统（H14系列）用于确定地图中每个螺柱保持的尺寸和公差。

The purpose of this MAP is to establish stud hold clearance diameters to accept standard Metric studs. This is based entirely on recommendations set forth by the International Organization for Standardization (I.S.O.). ISO Recommendations R273, Clearance Holes for Metric Bolts (Fine series) and R286, ISO System of Limits and Fits (H14 series) were used to establish the size and tolerance for each stud hold in the MAP.