Maximum Material Condition

The GD&T condition where a feature contains the most material — largest pin or smallest hole.

What it means on the floor

Maximum material condition (MMC) is the size limit at which a feature has the most material. When a position tolerance is applied at MMC, a bonus tolerance grows as the feature departs from MMC, allowing more location error while still guaranteeing assembly.

It is central to functional, assembly-based tolerancing of holes and pins.

Category: GD&T

Applying the term

Interpret Maximum Material Condition in the context of the drawing, governing standard, and customer requirement in front of you — the same word can carry different limits in design, quality, and production documents. Check whether a stated value is nominal, minimum, maximum, or reference-only, and whether it applies before forming, after forming, or after heat treatment.

Browse all manufacturing terms