Product Description
M6 Grade 10.9 Self Colour Countersunk Socket Set Screws – DIN 7991
M6 x 25mm fully threaded countersunk socket set screws manufactured from high-tensile property class 10.9 steel with a self-colour finish. Their flat countersunk heads are designed to sit flush with the surrounding surface when fitted into a correctly formed countersunk hole.
These screws have a standard M6 x 1.0 metric coarse thread and an internal hexagon drive operated using a 4mm Allen key or hexagon driver bit. They are listed as the DIN 7991 pattern commonly used for machinery, automotive and general engineering assemblies.
Key Features
- M6 metric coarse thread
- 1.0mm thread pitch
- 25mm overall length
- Property class 10.9 high-tensile steel
- Self-colour unplated finish
- Flat countersunk head
- Internal hexagon socket drive
- Fully threaded set-screw construction
- Listed as DIN 7991 pattern
- Available in packs from 5 to 1,000
Product Specifications
| Thread Size | Thread Pitch | Overall Length | Head Diameter | Head Height | Hex Key Size |
|---|---|---|---|---|---|
| M6 | 1.0mm | 25mm | 12mm | 3.3mm | 4mm |
Countersunk screw length is measured over the complete fastener, including the head.
Standards Information
This product is listed as a DIN 7991 countersunk socket screw. ISO 10642 is the corresponding international dimensional standard for this general fastener type. Standards should not be treated as interchangeable unless conformity is confirmed by the manufacturer or supporting certification.
Countersunk socket screws have reduced loadability at the head compared with standard socket-cap screws of the same thread size and property class. General grade 10.9 tightening figures should therefore not automatically be applied.
Self-Colour Finish
Self-colour steel does not provide the corrosion resistance of zinc plating or stainless steel. It is principally intended for dry indoor assemblies or applications where the fastener is protected using oil, grease, paint or another suitable surface treatment.
Typical Applications
- Machine guards and access panels
- Automotive assemblies
- Engineering machinery
- Jigs, fixtures and tooling
- Equipment housings
- Fabricated steel components
- Assemblies requiring a flush surface
Installation Advice
Confirm that the mating thread is M6 x 1.0 and that the component has a correctly sized 90-degree countersink. Install using a good-quality 4mm hexagon key or driver bit, keeping the tool fully engaged with the socket.
The complete countersunk head should seat evenly against the countersink. Avoid excessive tightening, particularly when fastening thin, soft or brittle materials.
Useful Links
- View all countersunk socket screws
- View metric countersunk socket screws
- M4 grade 10.9 self-colour countersunk socket screws
- M5 grade 10.9 self-colour countersunk socket screws
- M6 grade 10.9 zinc-plated countersunk socket screws
- Metric thread data guide
- How to measure a bolt or screw
Specifications are intended as a guide. Confirm the dimensions, material, finish, mechanical properties and certification before use in safety-critical or specification-controlled applications.
