为建立UNJ外形的公制模块版本，MIL-S-8879英寸螺纹标准，主要用于航空航天英寸设计。本标准规定了MJ型公制系列螺纹的特性，这些螺纹由ISO 68 M型改为，在外螺纹根部包括0.18042P至0.15011P的强制控制半径，并增加外螺纹和内螺纹的小直径，以提供0.5625H的基本螺纹高度，以适应外螺纹的最大根部半径。

To establish a metric module version of the UNJ profile, MIL-S-8879 inch screw thread standard, predominantly used in aerospace inch designs. This standard specifies the characteristics of the MJ profile metric series of screw threads, altered from ISO 68 M Profile, to include a mandatory controlled radius of 0.18042P to 0.15011P at the root of the external thread and with the minor diameter of both external and internal threads increased to provide a basic thread height of 0.5625H in order to accommodate the external thread maximum root radius.