ISO 10511Nylon insert lock nutExternal hexagon

ISO 10511 M12 Nylon insert lock nut

ISO 10511 M12 is a nylon insert lock nut, on a M12 × 1.5 mm metric thread. ISO equivalent of DIN 985. Reuse is limited — the prevailing torque drops each time the insert is run over the thread.

ISO 10511 M12 — Nylon insert lock nutNominal dimensions in mm · Not to scale

Diameter12 mm

Pitch1.5 mm

Socket size s18 mm

Thickness h16 mm

Height m15 mm

DriveExternal hexagon

Dimensions

Standard: ISO 10511
Type: Nylon insert lock nut
Size: M12
Thread: M12 × 1.5
Socket size s: 18 mm
Height m: 15 mm
Total height h: 16 mm
Drive: External hexagon

Nominal values in millimetres as published in ISO 10511. Estimated weight 11.462 g per piece in steel (11.535 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.

Thread data

Full M12 thread page

DesignationM12 × 1.5 fine

Pitch1.5 mm

Nominal Ø12 mm

Pitch Ø11.03 mm

Minor Ø ext10.16 mm

Tap drillØ 10.5 mm

Other lengthsISO 10511 M12

All M12 specifications

M12

Interchangeability

ISO 10511 is catalogued with DIN 985 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.

Equivalent standardDIN 985Prevailing Torque Hexagon Nut with Nylon Insert ComparisonISO 10511 vs DIN 985Field-by-field differences and a substitution verdict

Choosing and fitting this size

ISO 10511 M12 is a M12 nut, on a 1.5 mm coarse pitch. Mating threads should be a matching class nut in the same property class.

Common stock grades are 8.8, 10.9 and 12.9 in steel, plus A2-70 and A4-80 in stainless. Class 10.9 and 12.9 carry roughly 1.25 and 1.5 times the proof load of 8.8, but they also need a properly rated mating nut — a class 8 nut under a 12.9 bolt simply moves the failure into the thread. Zinc-plated 10.9 and above should be baked to avoid hydrogen embrittlement.

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.