DIN 986 Nylon Insert Dome Nuts
DIN 986 covers domed cap nuts with a nylon locking insert — combining the closed crown of a dome nut with insert locking. We supply DIN 986 nuts in steel property class 6 and stainless steel A2 across a wide range of metric sizes.
Also known as: Nyloc.
DIN 986 dimensions
| Diameter | Pitch | Overall height | Across Flats |
|---|---|---|---|
| M4 | 0.7mm | 9.6mm | 7mm |
| M5 | 0.8mm | 10.5mm | 8mm |
| M6 | 1.0mm | 12mm | 10mm |
| M8 | 1.25mm | 14mm | 13mm |
| M10 | 1.5mm | 18.1mm | 16mm |
| M12 | 1.75mm | 22.5mm | 18mm |
| M16 | 2mm | 27.5mm | 24mm |
| M20 | 2.5mm | 35mm | 30mm |
Materials & strength
Locking plus thread protection
The nylon ring resists vibration loosening while the closed dome covers the bolt end, protecting the thread and anyone who comes into contact with it.
Steel grade 6 & stainless A2
Grade 6 steel suits general fixing work; A2 stainless covers corrosive environments and exposed locations.
What is a DIN 986 dome nut?
DIN 986 is a domed cap nut with a nylon locking insert, combining a closed cap over the bolt end with the vibration resistance of a nylon insert. It tidies and protects the exposed thread while resisting loosening.
How much thread protrusion can a DIN 986 nut accept?
The cap is closed, so it limits how far the stud can protrude - the end must not bottom inside the dome before the nut clamps the joint. The internal depth available is less than the overall height shown in the table. Send us the stud protrusion and we can confirm suitability.
What is the difference between DIN 986, DIN 1587 and DIN 917 dome nuts?
DIN 1587 is the standard high-form dome nut and DIN 917 the low-form pattern, both plain; DIN 986 adds a nylon insert for locking. Choose by whether locking is needed and by the profile the assembly allows.
What materials are DIN 986 nuts available in?
DIN 986 nuts are available in steel grade 6 and stainless steel A2 across a wide range of metric sizes. Stainless suits damp or corrosive conditions where a plated steel nut is not appropriate.
Need DIN 986 in a non-standard size or material?
Send us your drawing — specials quoted within 24 hours.