DIN 913HeadlessHexagon socket

DIN 913 M6 × 20 Headless

DIN 913 M6 × 20 is a socket set screw, flat point with a 20 mm nominal length, on a M6 × 1 mm metric thread. A flat ended grub screw used where the shaft must not be marked, or for adjustment applications such as levelling screws.

DIN 913 M6 × 20 — HeadlessNominal dimensions in mm · Not to scale

Diameter6 mm

Length20 mm

Pitch1 mm

Socket size s3 mm

HeadHeadless

DriveHexagon socket

Dimensions

Standard: DIN 913
Type: Socket set screw, flat point
Size: M6 × 20
Thread: M6 × 1
Length L: 20 mm
Socket size s: 3 mm
Drive: Hexagon socket
Head: Headless

Nominal values in millimetres as published in DIN 913. Estimated weight 4.439 g per piece in steel (4.467 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.

Thread data

Full M6 thread page

DesignationM6 × 1

Pitch1 mm

Nominal Ø6 mm

Pitch Ø5.35 mm

Minor Ø ext4.77 mm

Tap drillØ 5 mm

Other lengthsDIN 913 M6

All M6 specifications

M6 × 6 M6 × 8 M6 × 10 M6 × 12 M6 × 16 M6 × 20 M6 × 25 M6 × 30

Interchangeability

DIN 913 is catalogued with ISO 4026 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.

Equivalent standardISO 4026Hexagon Socket Set Screw — Flat Point ComparisonDIN 913 vs ISO 4026Field-by-field differences and a substitution verdict

Choosing and fitting this size

DIN 913 M6 × 20 is a headless in M6, 20 mm long under the head, on a 1 mm coarse pitch. Mating threads should be a matching class nut or a tapped hole of the same nominal size.

Set screws are rated by surface hardness rather than tensile class — the common stock grade is 45H, which is hard enough to bite into a hardened shaft. Stainless set screws are not through-hardened and will not bite the same way, so they are a poor substitute where the point has to grip.

For a tapped hole, M6 × 1 mm takes a 5 mm tap drill, and the external thread's minor diameter is 4.77 mm — that is the section carrying the load, not the nominal M6 figure. Thread engagement of at least one times the nominal diameter is what lets the bolt fail before the thread strips.