本文件定义了最大材料要求（MMR）、最小材料要求（LMR）和互惠要求（RPR）。这些要求仅适用于圆柱型或两个平行相对平面型尺寸的线性特征。 这些要求通常用于控制尺寸和几何形状相互依赖的工件的特定功能，例如实现“零件装配”（对于MMR）或“最小壁厚”（对于LMR）功能。然而，MMR和LMR也可用于满足其他功能设计要求。

This document defines the maximum material requirement (MMR), the least material requirement (LMR) and the reciprocity requirement (RPR). These requirements can only be applied to linear features of size of cylindrical type or two parallel opposite planes type. These requirements are often used to control specific functions of workpieces where size and geometry are interdependent, for example to fulfil the functions “assembly of parts” (for MMR) or “minimum wall thickness” (for LMR). However, the MMR and LMR can also be used to fulfil other functional design requirements.