Product Description
M5 Grade 10.9 Self Colour Countersunk Socket Set Screws – DIN 7991
M5 x 16mm fully threaded countersunk socket set screws manufactured from high-tensile property class 10.9 steel with a self-colour finish. The flat countersunk head is designed to sit flush with the surrounding surface when installed in a correctly formed countersunk hole.
These screws have a standard M5 x 0.8 metric coarse thread and an internal hexagon drive operated using a 3mm Allen key or hexagon driver bit. They are listed as the DIN 7991 pattern commonly used for machinery, engineering and automotive assemblies.
Key Features
- M5 metric coarse thread
- 0.8mm thread pitch
- 16mm 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 |
|---|---|---|---|---|---|
| M5 | 0.8mm | 16mm | 10mm | 2.8mm | 3mm |
Unlike cap-head and hexagon-head fasteners, countersunk screw length is measured over the complete screw, 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 without confirming the manufacturer’s specification and certification.
Countersunk socket screws have reduced loadability at the head compared with standard cap-head screws of the same thread size and property class. General tightening figures for grade 10.9 hexagon or socket-cap fasteners should therefore not automatically be applied.
Self-Colour Finish
Self-colour steel does not have the corrosion protection provided by zinc plating or stainless steel. It is primarily intended for dry indoor assemblies or applications where the fastener is protected by oil, grease, paint or another suitable surface treatment.
Typical Applications
- Machine guards and access panels
- Automotive components
- Engineering assemblies
- Jigs, fixtures and tooling
- Equipment housings
- Fabricated steel components
- Applications requiring a flush surface
Installation Advice
Confirm that the mating thread is M5 x 0.8 and that the component has a correctly sized 90-degree countersink. Use a good-quality 3mm hexagon key or driver and keep it fully engaged with the socket during tightening.
The countersunk head should seat evenly against the complete countersink rather than bearing on one edge. Avoid excessive tightening, particularly in 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
- M6 grade 10.9 self-colour countersunk socket screws
- M5 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.
