DIN 985 / ISO 10511 nylon insert lock nut: dimensions
Prevailing torque hexagon thin nut with a non-metallic insert, from M3 to M24. Pick a size to get its dimensions and CAD files; where DIN 985 differs, switch to the DIN version.
ISO 10511 / DIN 985 nyloc nut dimensions
| Size | Pmm | snom, mm | emin, mm | hmax, mm | mmin, mm |
|---|---|---|---|---|---|
| M3 | 0.5 | 5.5 | 6.01 | 3.9 | 1.55 |
| M4 | 0.7 | 7 | 7.66 | 5 | 1.95 |
| M5 | 0.8 | 8 | 8.79 | 5 | 2.45 |
| M6 | 1 | 10 | 11.05 | 6 | 2.9 |
| M8 | 1.25 | 13 | 14.38 | 6.76 | 3.7 |
| M10 | 1.5 | 16 | 17.77 | 8.56 | 4.7 |
| M12 | 1.75 | 18 | 20.03 | 10.23 | 5.7 |
| M14 | 2 | 21 | 23.35 | 11.32 | 6.42 |
| M16 | 2 | 24 | 26.75 | 12.42 | 7.42 |
| M20 | 2.5 | 30 | 32.95 | 14.9 | 9.1 |
| M24 | 3 | 36 | 39.55 | 17.8 | 10.9 |
Where DIN 985 differs from ISO 10511
| Size | sISO 10511 | sDIN 985 | hISO 10511 | hDIN 985 | mISO 10511 | mDIN 985 |
|---|---|---|---|---|---|---|
| M3 | 5.5 | 5.5 | 3.9 | 4 | 1.55 | 2.4 |
| M4 | 7 | 7 | 5 | 5 | 1.95 | 2.9 |
| M5 | 8 | 8 | 5 | 5 | 2.45 | 3.2 |
| M6 | 10 | 10 | 6 | 6 | 2.9 | 4 |
| M8 | 13 | 13 | 6.76 | 8 | 3.7 | 5.5 |
| M10 | 16 | 17 | 8.56 | 10 | 4.7 | 6.5 |
| M12 | 18 | 19 | 10.23 | 12 | 5.7 | 8 |
| M14 | 21 | 22 | 11.32 | 14 | 6.42 | 9.5 |
| M16 | 24 | 24 | 12.42 | 16 | 7.42 | 10.5 |
| M20 | 30 | 30 | 14.9 | 20 | 9.1 | 14 |
| M24 | 36 | 36 | 17.8 | 24 | 10.9 | 15 |
DIN 985 is withdrawn but parts to it are still sold. Only the sizes listed here differ; in every other size both standards give the same part. Pick the standard in the selector above to get the matching CAD files.
Dimensions in millimetres unless stated. Select a row to load its CAD files above.
ISO 10511 vs DIN 985
DIN 985 nuts are taller than ISO 10511 in several sizes, and the width across flats changes in M10, M12, M14 and M22. At M8, for example, the ISO nut is up to 6.76 mm high in total and the DIN nut up to 8 mm. The DIN 985 sizes have their own CAD files, listed under the table.
Nyloc nut dimensions: total height and thread height
The table gives two heights. The total height h includes the collar that holds the nylon ring; the height m is the minimum length of the metal thread below it. The insert is slightly smaller than the thread, so the bolt cuts its own thread into it and the friction holds the nut. Allow at least two threads of the bolt to show through the nut so the insert is fully engaged.
DIN 985 and ISO 10511 are the low type. The high type, DIN 982 or ISO 7040, has a taller metal part for higher loads.
DIN 985 lock nuts: common questions
- What is the difference between DIN 982 and DIN 985?
- Both are nylon insert lock nuts. DIN 985 is the low type, with a thread about as long as a thin nut; DIN 982 is the high type, with a thread as long as a regular nut.
- What are the dimensions of an M12 nyloc nut?
- An ISO 10511 M12 nut is 18 mm across flats and up to 10.23 mm high, with at least 5.7 mm of metal thread. The DIN 985 version is 19 mm across flats and up to 12 mm high.