GD&T · Modifier · ASME Y14.5
Maximum Material Condition (MMC) GD&T Symbol — Meaning and Datum Rule
https://shopmath.org/gdt/maximum-material-condition · data verified August 1, 2026
Maximum Material Condition (MMC) (Ⓜ) is a GD&T modifier: it changes how a tolerance is interpreted rather than defining a zone of its own. It never references a datum.
- Symbol
- Ⓜ
- Unicode
- U+24C2
- Category
- Modifier
- Datum
- never
Maximum Material Condition (MMC) · GD&T modifier symbol
Ⓜ
- Unicode
- U+24C2
- Datum
- never
Maximum Material Condition (MMC) qualifies another tolerance rather than standing on its own — it appears after the tolerance value or the datum reference it modifies.
What Maximum Material Condition (MMC) Controls in GD&T
States that the stated tolerance applies when the feature contains the most material — the largest pin or the smallest hole. As the feature departs from that limit the difference becomes bonus tolerance and is added to the geometric tolerance, which is what makes a functional gauge a valid acceptance method.
The Maximum Material Condition (MMC) GD&T Symbol, Zone and Datum Rule
The symbol as it appears in the feature control frame, with the codepoint to type it and the rule it carries.
| Property | Value |
|---|---|
| Symbol | Ⓜ |
| Unicode codepoint | U+24C2 (CIRCLED LATIN CAPITAL LETTER M) |
| Category | Modifiers and material conditions — Change how a geometric tolerance is interpreted or verified. |
| Tolerance zone | n/a — modifier |
| Datum reference | Never references a datum. The tolerance zone floats to best-fit the feature, so this control says nothing about where the feature sits relative to anything else. |
| Standard | ASME Y14.5 (cited, not reproduced); ISO 1101 |
| Also called | mmc gdt, maximum material condition, mmc vs lmc |
The symbol character is the Unicode codepoint used in drawings and CAD annotations; drafting standards render it with defined proportions that the font approximates.
Sources and Method for the Maximum Material Condition (MMC) GD&T Reference
- Maximum Material Condition (MMC) symbol and rulescompiled
Symbols and codepoints: Unicode Character Database (Unicode License v3). Characteristic list cross-checked against NASA MSFC GD&T Basics (public domain). Descriptions written from scratch; no ASME Y14.5 text reproduced.
Verified against Unicode Character Database codepoint check; 98/98 structural checks passed
Compiled from independent public sources that agree cell-for-cell.
- Assumptions
- The standard is cited, never reproduced: no ASME Y14.5 definitional text, worked example or figure appears on this site. The description above is original prose.
- ASME Y14.5 and ISO 1101 differ in places — the ISO system uses the envelope requirement differently and does not carry every ASME modifier. Where a drawing names a standard, that standard governs.
- Dataset scope: EXCLUDED: all ASME Y14.5 definitional text, worked examples and figures. Every description on this site is original prose.
- Data last verified
- August 1, 2026
How to Cite This Maximum Material Condition (MMC) GD&T Reference
Citation
ShopMath. "Maximum Material Condition (MMC) GD&T Symbol — Meaning and Datum Rule." ShopMath, verified August 1, 2026, https://shopmath.org/gdt/maximum-material-condition
BibTeX
@misc{shopmath-gdt-maximum-material-condition,
title = {Maximum Material Condition (MMC) GD&T Symbol — Meaning and Datum Rule},
author = {{ShopMath}},
year = {2026},
howpublished = {\url{https://shopmath.org/gdt/maximum-material-condition}},
note = {Data verified 2026-08-01}
}Permanent URL
https://shopmath.org/gdt/maximum-material-condition
Common Questions About Maximum Material Condition (MMC) in GD&T
What does Maximum Material Condition (MMC) mean in GD&T?
- States that the stated tolerance applies when the feature contains the most material — the largest pin or the smallest hole. As the feature departs from that limit the difference becomes bonus tolerance and is added to the geometric tolerance, which is what makes a functional gauge a valid acceptance method.
What is the Maximum Material Condition (MMC) symbol in GD&T?
- Ⓜ — Unicode U+24C2 (CIRCLED LATIN CAPITAL LETTER M). It goes in the first compartment of the feature control frame, ahead of the tolerance value.
Does Maximum Material Condition (MMC) need a datum?
- Never references a datum. The tolerance zone floats to best-fit the feature, so this control says nothing about where the feature sits relative to anything else.
Which GD&T modifiers are in the same group as Maximum Material Condition (MMC)?
- Maximum Material Condition (MMC) is one of 8 modifier modifiers: Maximum Material Condition (MMC), Least Material Condition (LMC), Regardless of Feature Size (RFS), Projected Tolerance Zone, Free State, Tangent Plane, Unequally Disposed Profile, Diameter.