ISO 10511 specifies thin hexagon nuts with a nylon insert — prevailing torque lock nuts that resist loosening from vibration. The current standard is ISO 10511; the legacy German designation is DIN 985, and in our compiled data all 22 sizes from M3 to M48 match between the two. This page gives the complete dimension table with heights, across-flats, across-corners and theoretical weight per 1,000 pieces.
| Parameter (mm) | M3 | M4 | M5 | M6 | M7 | M8 | M10 | M12 | M14 | M16 | M18 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| P — pitch (mm) | 0.5 | 0.7 | 0.8 | 1 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2 | 2.5 |
| da — max | 3.45 | 4.6 | 5.75 | 6.75 | 7.75 | 8.75 | 10.8 | 13 | 15.1 | 17.3 | 19.5 |
| da — min | 3 | 4 | 5 | 6 | 7 | 8 | 10 | 12 | 14 | 16 | 18 |
| dw — min | 4.6 | 5.9 | 6.9 | 8.9 | 9.6 | 11.6 | 15.6 | 17.4 | 20.5 | 22.5 | 24.9 |
| e (across corners) — min | 6.01 | 7.66 | 8.79 | 11.05 | 12.12 | 14.38 | 18.9 | 21.1 | 24.49 | 26.75 | 29.56 |
| h — height max | 4 | 5 | 5 | 6 | 7.5 | 8 | 10 | 12 | 14 | 16 | 18.5 |
| h — height min | 3.7 | 4.7 | 4.7 | 5.7 | 7.14 | 7.64 | 9.64 | 11.57 | 13.3 | 15.3 | 17.66 |
| m — min | 2.4 | 2.9 | 3.2 | 4 | 4.7 | 5.5 | 6.5 | 8 | 9.5 | 10.5 | 13 |
| m′ — min | 1.65 | 2.2 | 2.75 | 3.3 | 3.85 | 4.4 | 5.5 | 6.6 | 7.7 | 8.8 | 9.9 |
| s (across flats) — nominal = max | 5.5 | 7 | 8 | 10 | 11 | 13 | 17 | 19 | 22 | 24 | 27 |
| s — min | 5.32 | 6.78 | 7.78 | 9.78 | 10.73 | 12.73 | 16.73 | 18.67 | 21.67 | 23.67 | 26.16 |
| Weight — kg / 1,000 pcs | 0.5 | 1 | 1.4 | 2.4 | 3 | 5.1 | 10.6 | 17.2 | 26 | 34 | 45 |
Source: DIN 985 / ISO 10511 compiled table (see Sources). Dimensions in millimetres; weight is a theoretical estimate per 1,000 pieces.
| Parameter (mm) | M20 | M22 | M24 | M27 | M30 | M33 | M36 | M39 | M42 | M45 | M48 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| P — pitch (mm) | 2.5 | 2.5 | 3 | 3 | 3.5 | 3.5 | 4 | 4 | 4.5 | 4.5 | 5 |
| da — max | 21.6 | 23.7 | 25.9 | 29.1 | 32.4 | 35.6 | 38.9 | 42.1 | 45.4 | 48.6 | 51.8 |
| da — min | 20 | 22 | 24 | 27 | 30 | 33 | 36 | 39 | 42 | 45 | 48 |
| dw — min | 27.7 | 29.5 | 33.2 | 38 | 42.7 | 46.6 | 51.1 | 55.9 | 60.6 | 64.7 | 69.4 |
| e (across corners) — min | 32.95 | 35.03 | 39.55 | 45.2 | 50.85 | 55.37 | 60.79 | 66.44 | 72.09 | 76.95 | 82.6 |
| h — height max | 20 | 22 | 24 | 27 | 30 | 33 | 36 | 39 | 42 | 45 | 48 |
| h — height min | 18.7 | 20.7 | 22.7 | 25.7 | 28.7 | 31.4 | 34.4 | 37.4 | 40.4 | 43.4 | 46.4 |
| m — min | 14 | 15 | 15 | 17 | 19 | 22 | 25 | 27 | 29 | 32 | 36 |
| m′ — min | 11 | 12.2 | 13.2 | 14.8 | 16.5 | 18.2 | 19.8 | 21.5 | 23.1 | 24.8 | 26.5 |
| s (across flats) — nominal = max | 30 | 32 | 36 | 41 | 46 | 50 | 55 | 60 | 65 | 70 | 75 |
| s — min | 29.16 | 31 | 35 | 40 | 45 | 46 | 53.8 | 58.8 | 63.8 | 68.1 | 73.1 |
| Weight — kg / 1,000 pcs | 65 | 75 | 100 | 162 | 212 | 317 | 415 | 499 | 628 | 771 | 998 |
Source: DIN 985 / ISO 10511 compiled table (see Sources). Dimensions in millimetres; weight is a theoretical estimate per 1,000 pieces.
The standard also covers fine-pitch versions of some sizes; available combinations include: M8x1, M10x1, M10x1,25, M12x1,5, M12x1,25, M14x1,5, M16x1,5, M18x2, M18x1,5, M20x2, M20x1,5, M22x2, M22x1,5, M33x2, M36x3, M39x3, M42x3, M45x3, M48x3. State the pitch when ordering — the table above shows the coarse pitch P.
The nylon insert grips the bolt thread and creates a prevailing torque, so the nut does not back off under vibration. The thin (DIN 985 / ISO 10511) version is used where nut height is limited; where more thread engagement is needed, use the standard-height DIN 982 / ISO 7040 type. The insert is a non-metallic (nylon) ring — check the service temperature with us for hot applications.
Supplied in carbon steel and stainless steel (A2 / A4) with zinc plating, hot-dip galvanizing, zinc-nickel or dacromet finishes. The standard covers metric sizes and a range of property classes; confirm the class and coating on the drawing or order — see mechanical properties and surface treatment.
State the standard (ISO 10511 or the equivalent), size and pitch, material / grade, finish and quantity. For hot applications, tell us the service temperature so the insert material can be confirmed.
ISO 10511 specifies thin hexagon nuts with a non-metallic (nylon) insert — prevailing torque nuts for vibration resistance. It is the current international standard behind the legacy DIN 985 designation.
Dimensionally yes — in our compiled data all 22 sizes from M3 to M48 match DIN 985. Use ISO 10511 for new drawings and DIN 985 where the old designation is called out.
ISO 10511 is the thin type; ISO 7040 is the standard-height type (DIN 982). Choose by the height available and the thread engagement required.
ISO 10511 M10: s = 17 mm, h = 10 mm, e = 18.9 mm, about 10.6 kg per 1,000 pieces.
h is the overall nut height, m the minimum thickness at the bearing face, m′ the minimum thickness at the top face, and s the width across flats.
Yes — fine pitch options are listed in the table notes (e.g. M10x1, M10x1.25, M12x1.5, M12x1.25). State the pitch on the order.
The last row gives the theoretical weight per 1,000 pieces — e.g. M10 about 10.6 kg, M30 about 212 kg per 1,000.
Yes — A2 / A4 stainless steel and zinc plated, hot-dip galvanized, zinc-nickel or dacromet finishes. The nylon insert has a service-temperature limit, so tell us the application temperature.
Dimensions and weights: ISO 10511 / ISO 10511 compiled table (source: fasteners.eu, retrieved 2026-10-30); DIN 985 and ISO 10511 verified size-by-size identical (22/22). Weight values are theoretical per 1,000 pieces. Page last reviewed: 2026-10-30.