M3 nyloc nut in A2 stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A2 (304 grade) gives good corrosion resistance for indoor and non-coastal outdoor use. Free next-day UK delivery on orders over £50.
  • M3 nyloc nut A2 stainless DIN 985
  • DIN 985 nylon insert nut M3 A2 stainless steel, side view
  • Nylon insert detail - M3 A2 stainless nyloc nut DIN 985
  • Simfix product label - 985A203PK20-SIM
  • Simfix product label - 985A203PK100-SIM
M3 nyloc nut A2 stainless DIN 985
DIN 985 nylon insert nut M3 A2 stainless steel, side view
Nylon insert detail - M3 A2 stainless nyloc nut DIN 985
Simfix product label - 985A203PK20-SIM
Simfix product label - 985A203PK100-SIM

Simfix

Nylon Insert Nut DIN 985 A2 Stainless Steel (M3)

SKU 985A203PK20-SIM
£1.55
Pack size:
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M3 nyloc nut in A2 stainless steel to DIN 985. The nylon insert grips the bolt thread under vibration and dynamic loading, resisting loosening without thread locking compound - and re-usable after removal. A2 (304 grade) gives good corrosion resistance for indoor and non-coastal outdoor use. Free next-day UK delivery on orders over £50.
£1.55
M3 nyloc nut A2 stainless DIN 985 DIN 985 nylon insert nut M3 A2 stainless steel, side view Nylon insert detail - M3 A2 stainless nyloc nut DIN 985 Simfix product label - 985A203PK20-SIM Simfix product label - 985A203PK100-SIM
M3 nyloc nut A2 stainless DIN 985 DIN 985 nylon insert nut M3 A2 stainless steel, side view Nylon insert detail - M3 A2 stainless nyloc nut DIN 985 Simfix product label - 985A203PK20-SIM Simfix product label - 985A203PK100-SIM

This M3 nyloc lock nut is manufactured to DIN 985 in A2 stainless steel (304 grade). DIN 985 specifies a standard hex nut body with a nylon insert in the upper portion of the thread. As the bolt passes through, the nylon insert deforms around the thread and creates a prevailing torque that resists loosening under vibration and dynamic loading. Unlike chemical thread lock, the nylon insert remains effective after removal and re-fitting multiple times, making it practical for assemblies that require periodic maintenance access.

Typical applications

  • Mechanical assemblies subject to vibration, where a standard nut would loosen
  • Automotive, machinery, and general engineering applications
  • Workshop equipment, bicycle and cycle components, and jig frames
  • General indoor and outdoor fixings where vibration or movement is a risk

Available in packs of 20 to 100, with free next-day UK delivery on orders over £50 and 30-day no-quibble returns.

Fastener styleNyloc insert lock nut
StandardDIN 985
MaterialA2 stainless steel (304)
Property classA2
Thread sizeM3
Thread pitch0.5 mm (coarse)
Head typeHexagon
Drive typeExternal hex (spanner)
Surface finishPlain (no plating)
HS commodity code7318163990
Recommended useWorkshop

RoHS and REACH compliant.

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