Material
Carbon Steel
Type
Extended hex coupling nut
Size Range
M5–M24
Surface Finish
Plain / Zinc / H.D.G
Class
6 / 8 / 10
Standard
DIN 6334
Packaging
Carton / Pallet
MOQ
1 piece (sample)
Precision Manufacturing, Batch After Batch
From cold-heading raw steel wire to heat-treated finished bolts, every step runs under strict in-house process control — ensuring the dimensional accuracy and strength grade printed on every head marking.
Product Overview
Application Scenarios
Hex long nuts (DIN 6334), also called coupling or extension nuts, are roughly three times the length of a standard nut with a continuous through thread — they join two lengths of threaded rod or two bolts end-to-end into one longer assembly. Widely used to extend anchor rods, build threaded-rod frameworks and connect studs in construction, scaffolding and machinery. The extra length gives more thread engagement and a stronger, self-aligning coupling.
Installation Notes
Thread each rod in from opposite ends until they meet near the middle — aim for both rods to engage at least one bolt-diameter of thread inside the nut for full strength. A sight hole or checking the gap helps confirm equal engagement. Use thread-locker or a jam nut against each end on vibration-prone joints, and match the coupling nut class to the rod grade so the coupling is as strong as the rod.
Material & Certification
Manufactured from carbon steel to property class 6, 8 or 10 per ISO 898-2 and produced to DIN 6334, with a continuous through thread for coupling two rods or studs. Every batch is traceable to raw material certificates; each run passes 100% dimensional and thread-gauge inspection; EN 10204 3.1 certificates available on request.
Hex Long / Coupling Nut
Carbon Steel Long / Coupling Nut · Class 6 / 8 / 10 · DIN 6334
Dimensional Specifications
DIN 6334 Standard Reference Dimensions — click a size to locate it below
| Thread Size | Width Across Flats s (mm) | Length L (mm) |
|---|---|---|
| M5 | 8 | 16 |
| M6 | 10 | 18 |
| M8 | 13 | 24 |
| M10 | 17 | 30 |
| M12 | 19 | 36 |
| M16 | 24 | 48 |
Reference dimensions per DIN 6334 standard. Full size range M5–M24 available on request — contact us for custom specification sheets.
Applications
Construction
Steel structures, bridges, buildings, concrete anchors
Machinery
Heavy equipment, industrial machines, manufacturing
Infrastructure
Railways, towers, pipelines, power transmission
Automotive
Vehicle assembly, chassis, engine components
Trusted By Global Buyers
Factory-direct hex long / coupling nuts exported to construction, machinery and infrastructure buyers across Europe, Africa, Asia and the Americas.