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Knurled Thumb Screw Dimensions, Low Type (DIN 653, M2 to M10)
Guide · Updated October 28, 2026
DIN 653 covers low (flat) type knurled thumb screws, M1 to M10; this chart shows M2 to M10. Knurl diameter and head height agree across fasteners.eu, Fuller Fasteners, Ferrobend, Ganter and DIV Group tables; ds and a max match fasteners.eu, Fuller and Ferrobend. Nominal sizes shown.
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Step by step
- Find the thread: Pick the row for your tapped hole, M2 to M10.
- Check the grip: dk is the knurl diameter, e.g. 24 mm for M6.
- Check the head height: k is the whole head height, e.g. 5 mm for M6; there is no collar.
- Allow the run-out: The last a max of thread under the head may be incomplete; keep it out of the tapped hole.
DIN 653 knurled thumb screw dimensions (mm)
Columns: thread d, pitch P, knurl diameter dk, head height k max, neck diameter ds max, thread run-out a max.
- Size | P | dk | k | ds | a max
- M2 | 0.4 | 9 | 2 | 2 | 1.2
- M2.5 | 0.45 | 11 | 2.5 | 2.5 | 1.35
- M3 | 0.5 | 12 | 2.5 | 3 | 1.5
- M4 | 0.7 | 16 | 3.5 | 4 | 2.1
- M5 | 0.8 | 20 | 4 | 5 | 2.4
- M6 | 1 | 24 | 5 | 6 | 3
- M8 | 1.25 | 30 | 6 | 8 | 3.75
- M10 | 1.5 | 36 | 8 | 10 | 4.5
Worked example: M6 screw
An M6 DIN 653 screw has a 24 mm knurled head only 5 mm tall. Up to 3 mm of thread under the head may be run-out, so a 12 mm screw gives about 9 mm of full thread.
Common problems
- Over-tightening with pliers: these are for hand torque only.
- Hard to grip: the low head gives less finger grip; step to DIN 464 if needed.
- Screw vibrates loose: add a spring washer or thread locker.
FAQ
What is DIN 653 used for?
Low profile hand screws for covers, panels and instruments where a tall head would be in the way.
DIN 653 vs DIN 464?
Same knurl diameter and k per size; DIN 464 adds a collar ds, making the head 15 mm tall at M6 instead of 5 mm.
What is ds on a DIN 653 screw?
The neck diameter under the head, equal to the thread size at max.
Why are sizes below M2 left out?
The standard lists M1 to M1.6 too, but most free sources and suppliers start at M2 or M3, so this chart starts at M2.
Related guides and calculators
- Wing screws (DIN 316)
- High knurled thumb screws (DIN 464)
- Tall knurled thumb nuts (DIN 466)
- Thin knurled thumb nuts (DIN 467)
- Knurled nuts (DIN 6303)
- How to knurl on a lathe
- All free machinist calculators
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