Size picker · Hex socket drive · DIN 7984
Low head cap screw sizes.
Half the head height of a standard cap screw, for when the counterbore is shallow or the clearance is not there. Pick a diameter and length for the head figures and the key size — and note the key is smaller than a DIN 912 of the same thread.
1 Pick a diameter
2 Pick a length
Choose a diameter first.
Your browser could not draw the 3D view. The dimensions beside it are unaffected.
Drawn to proportion from the standard dimensions. Illustration, not a photograph of the item.
Selected
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| Sym | Dimension | Value |
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Job stopped? Ring 01327 877577 and we'll check the stock while you're on.
Read the full DIN 7984 size chart
| Size | 3 | 4 | 5 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 90 | 100 | 130 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | |||||||||||||||||||||||||||
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| M5 | |||||||||||||||||||||||||||
| M6 | |||||||||||||||||||||||||||
| M8 | |||||||||||||||||||||||||||
| M10 | |||||||||||||||||||||||||||
| M12 | |||||||||||||||||||||||||||
| M14 | |||||||||||||||||||||||||||
| M16 | |||||||||||||||||||||||||||
| M20 |
The range shown is what fastener wholesalers commonly list — not a claim about what the standard mandates, and not a stock list. In-between lengths (85, 95, 170…), lengths past 300mm and odd diameters like M7 are made too, and availability varies by finish and grade — ask us for anything you can't see.
The trap: the key size changes
A low head screw does not take the same Allen key as the cap screw of the same thread. An M10 DIN 7984 takes a 7mm key where an M10 DIN 912 takes 8mm; M12 takes 8mm against 10mm. Order the keys with the screws if the fitters do not carry a full set.
The shallow head also carries less. The standard covers class 8.8; 10.9 is widely sold but sits outside the DIN 7984 text. If the joint is at its limit, use a standard cap screw and deepen the counterbore.
Not sure which you need?
Bring the old one in and we will match it at the counter — Baird Close, Daventry.
More size charts
Every size, drawn to scale.
Hex setscrews
DIN 933 · full thread
Hex bolts
DIN 931 · part thread
Socket cap screws
DIN 912
Button head screws
ISO 7380-1
Flanged button heads
ISO 7380-2
Countersunk socket screws
DIN 7991
Grub screws
DIN 913–916 · five points
Nuts
DIN 934 · nyloc · thin · Stover · flange
Washers
ISO 7089 · BS 4320 · penny
Not sure what the markings on the head mean? Bolt grades explained covers 8.8, 10.9, 12.9, stainless A2 and A4, and the imperial SAE grades.
All of it comes off the shelf at Baird Close — see the full fasteners & fixings range, or every size guide.