Countersunk screws to DIN 7991 / ISO 10642 have a countersunk head with a hexagon socket: the head sits fully inside the counterbore and the surface stays flush. In stock we carry the size M8x60 with full thread in steel 8.8, Geomet-coated. Further sizes up to M12, including stainless steel, are available on request. B2B terms, fastening specialist since 1943.
Hexagon socket countersunk screw M8x60, fully threaded, steel, property class 8.8, Geomet-coated
Content: 1 piece (€57.986300 / 100 piece)
Why Geomet and not hot-dip here
A hot-dip zinc layer of 45 to 85 µm would settle in exactly the two places this screw depends on: the countersink, where the head has to finish flush, and the hexagon socket, where the key has to fit. Geomet is a thin zinc flake coating and keeps both dimensions — which is why the stocked version is Geomet-coated and not hot-dip galvanized.
Where a flush head is required
Wherever nothing may stand above the surface and a protruding head would catch. Where the head may protrude, the hexagon screw is the simpler choice, and where the bolt must not turn, the cup square bolt.
Frequently asked questions
Which standard do the countersunk screws comply with?
The countersunk screws comply with DIN 7991 / ISO 10642 – countersunk head with hexagon socket, full thread.
What is the difference between DIN 7991 and ISO 10642?
It is the same screw: ISO 10642 is the internationally harmonized equivalent of the German standard DIN 7991. Dimensions and head shape are identical.
What is a countersunk screw used for?
The countersunk head disappears completely into the countersink so that the joint finishes flush and nothing protrudes above the surface. That is required wherever people walk or drive over the surface or where it is cleaned – for example on gratings and covers.
Which dimension and property class is in stock?
In stock in this shop: M8 x 60 mm in steel 8.8, Geomet-coated. From the ARNELL range on request: M4 to M12, steel 8.8 and 10.9, stainless steel 1.4301 and 1.4404, Geomet-coated or electroplated.
What is a Geomet coating?
Geomet is a thin zinc flake coating. It is more dimensionally accurate than hot-dip galvanizing and avoids the risk of hydrogen embrittlement on high-strength screws – which makes it the matching surface for property class 8.8.