← AskMachinist · Guides · Calculator · 🔎 Search
Wing Nut Dimensions (DIN 315, M4 to M24)
Guide · Updated October 28, 2026
DIN 315 covers German-type wing nuts with rounded wings, from M4 to M24. The max values agree across fasteners.eu, Aspen Fasteners and RC Fastener (to M20), and Whole-Spec confirms M4 to M10. Check your supplier for critical work.
Need an exact reference size?
Build any gage block stack with the free Gage Block Calculator. Free, no login.
Step by step
- Match the thread: Check the bolt size and coarse pitch.
- Check clearance: Allow for the wing span e and height h in the space around the nut.
- Hand tighten: Turn the wings with your fingers. Do not use pliers.
- Mind vibration: A wing nut loosens under vibration, so add a lock washer.
- Check thread length: The bolt must pass fully through the nut.
DIN 315 wing nut dimensions (mm)
Columns: thread, pitch P, boss diameter d2 max, wing span e max, height h max, wing thickness g max.
- Size | P | d2 max | e max | h max | g max
- M4 | 0.7 | 8 | 20 | 10.5 | 1.9
- M5 | 0.8 | 11 | 26 | 13 | 2.3
- M6 | 1 | 13 | 33 | 17 | 2.3
- M8 | 1.25 | 16 | 39 | 20 | 2.8
- M10 | 1.5 | 20 | 51 | 25 | 4.4
- M12 | 1.75 | 23 | 65 | 33.5 | 4.9
- M16 | 2 | 29 | 73 | 37.5 | 6.4
- M20 | 2.5 | 35 | 90 | 46.5 | 6.9
- M24 | 3 | 44 | 110 | 56.5 | 9.4
Worked example: M8 wing nut
An M8 DIN 315 wing nut spans up to 39 mm across the wings and stands up to 20 mm tall, so leave about 40 mm of finger room around it.
Common problems
- Wings bend: you overtightened it with a tool.
- Nut backs off: add a spring washer.
- Will not fit: check the clearance for e.
FAQ
What is DIN 315?
The German-type wing nut (butterfly nut) with rounded wings, for hand tightening.
Why is M14 missing?
Aspen lists 28/72/36 and RC Fastener lists 29/73/37.5, and fasteners.eu has no M14, so that size is not charted.
Why only max values?
Min values and the body height m come from one table only, so they are skipped.
Is the JIS wing nut the same?
No. JIS B 1185 sizes differ slightly.
Materials?
Steel, stainless A2 or A4, brass, or malleable cast iron.
Related guides and calculators
- Knurled thumb nuts, tall (DIN 466)
- Knurled thumb nuts, thin (DIN 467)
- Slotted round nuts (DIN 546)
- Hex coupling nuts (DIN 6334)
- Hex nuts (ISO 4032)
- Jam nuts (ISO 4035)
- Domed cap nuts (DIN 1587)
- All free machinist calculators
Build your stack in seconds
The free Gage Block Calculator finds the fewest-block combination for inch and metric sets, with wear blocks. No login.
Questions? Ask a machinist.
General shop information only — follow your drawing, tool maker's data and your quality system.