ISO 4026 M12 × 25 Headless
ISO 4026 M12 × 25 is a socket set screw, flat point with a 25 mm nominal length, on a M12 × 1.5 mm metric thread. ISO flat point counterpart to DIN 913. The plain disc end bears on the shaft without cutting into it, so it suits joints that are adjusted repeatedly or shafts whose surface has to stay undamaged. Body dimensions are shared with the cup point page — all four point styles use the same thread and socket sizes.
Dimensions
- Standard
- ISO 4026
- Type
- Socket set screw, flat point
- Size
- M12 × 25
- Thread
- M12 × 1.5
- Length L
- 25 mm
- Socket size s
- 6 mm
- Drive
- Hexagon socket
- Head
- Headless
Nominal values in millimetres as published in ISO 4026. Estimated weight 22.195 g per piece in steel (22.337 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.
Thread data
Full M12 thread pageOther lengthsISO 4026 M12
All M12 specificationsInterchangeability
ISO 4026 is catalogued with DIN 913 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.
Choosing and fitting this size
ISO 4026 M12 × 25 is a headless in M12, 25 mm long under the head, on a 1.5 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, M12 × 1.5 mm takes a 10.5 mm tap drill, and the external thread's minor diameter is 10.16 mm — that is the section carrying the load, not the nominal M12 figure. Thread engagement of at least one times the nominal diameter is what lets the bolt fail before the thread strips.