Source: https://www.quantumsteeldesign.com/steel-tools/shapes/m/ 16 AISC v16.0 records # AISC Miscellaneous beams (M). An M-shape is a miscellaneous doubly symmetric section that does not fit the standard W or S series proportions. The exact AISC record—not the nominal depth alone—defines its geometry and properties. ## Common context Common project roles are project-specific and may include specialty beams, industrial framing, existing-condition matches, and members selected for unusual proportions. ## Detailing watch Verify exact designation, availability, flange geometry, gage, connection compatibility, and substitution criteria before detailing or procurement. Use the directory as a reference ## How to read the M records M is a separate miscellaneous beam series. Use the exact designation and dimensions; a matching nominal depth in another family is insufficient for a geometry match. Record web and flange dimensions alongside weight, and confirm the specified section is available before procurement. This dataset contains 16 M records, with nominal weights from 2.9 to 18.9 lb/ft and listed depth values from 3 to 12.5 in. These ranges describe the published records, not current supplier inventory or a selection recommendation. Start with the exact designation, open its full record, then compare only the dimensions and properties relevant to your task. For example, [M8X6.5](https://www.quantumsteeldesign.com/steel-tools/shapes/m8x6-5/) lists 6.5 lb/ft, 1.92 in² area, Ix = 18.5 in⁴ and Iy = 0.376 in⁴. The x and y labels retain the database axes; their values do not establish allowable loads. The [AISC v16.0 workbook Readme](https://www.aisc.org/aisc/publications/steel-construction-manual/aisc-shapes-database-v160/) defines the variables and shape figures. This directory uses the US customary record; the comparison tool converts displayed units. Check the required edition and product specification before transferring data. Worked quantity example ## Nominal weight for M8X6.5 Assume 3 pieces, each 20 ft (6.096 m) long. This is a hypothetical quantity example, not a stock-length or lifting recommendation. | Quantity | Calculation | Nominal pounds | Kilogram equivalent | | --- | --- | --- | --- | | One 20 ft piece | 20 ft × 6.5 lb/ft | 130 lb | 58.967 kg | | 3 pieces | 3 × 130 lb | 390 lb | 176.901 kg | Conversion: 1 lb = 0.45359237 kg; displayed results are rounded. This multiplication excludes connection plates, bolts, weld metal, coatings, cutting allowances and actual material variation. Use the [material takeoff](https://www.quantumsteeldesign.com/material-takeoff/) for your own lengths and quantities. Crawlable designation index ## All M shape records. [View all shape families](https://www.quantumsteeldesign.com/steel-tools/shapes/) Filter by designation Showing all 16 records. | Designation | Weight | Depth / OD / d | Area | X-axis Sx | | --- | --- | --- | --- | --- | | M12.5X12.4 | 12.4 lb/ft | 12.5 in | 3.63 in² | 14.2 in³ | | M12.5X11.6 | 11.6 lb/ft | 12.5 in | 3.4 in² | 12.8 in³ | | M12X11.8 | 11.8 lb/ft | 12 in | 3.47 in² | 12 in³ | | M12X10.8 | 10.8 lb/ft | 12 in | 3.18 in² | 11.1 in³ | | M12X10 | 10 lb/ft | 12 in | 2.95 in² | 10.3 in³ | | M10X9 | 9 lb/ft | 10 in | 2.65 in² | 7.79 in³ | | M10X8 | 8 lb/ft | 9.95 in | 2.37 in² | 6.95 in³ | | M10X7.5 | 7.5 lb/ft | 9.99 in | 2.22 in² | 6.6 in³ | | M8X6.5 | 6.5 lb/ft | 8 in | 1.92 in² | 4.63 in³ | | M8X6.2 | 6.2 lb/ft | 8 in | 1.82 in² | 4.39 in³ | | M6X4.4 | 4.4 lb/ft | 6 in | 1.29 in² | 2.41 in³ | | M6X3.7 | 3.7 lb/ft | 5.92 in | 1.09 in² | 2.01 in³ | | M5X18.9 | 18.9 lb/ft | 5 in | 5.56 in² | 9.67 in³ | | M4X6 | 6 lb/ft | 3.8 in | 1.75 in² | 2.48 in³ | | M4X4.08 | 4.08 lb/ft | 4 in | 1.27 in² | 1.77 in³ | | M3X2.9 | 2.9 lb/ft | 3 in | 0.914 in² | 1 in³ | Reference use only. Values are derived from the [AISC Shapes Database v16.0](https://www.aisc.org/aisc/publications/steel-construction-manual/aisc-shapes-database-v160/) in US customary units. Open a designation for its full property table, nominal profile, downloads, source notes, and limitations.