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DIN 935-1 M12 castle nut (collar Ø16)

DIN 935-1 M12 castle nut (collar Ø16): hex 18 mm across flats, height 15, unslotted height 10, six slots 3.8 mm wide (n max) and 5 mm deep, bore Ø12 (thread major diameter as a plain cylinder); no chamfers, no thread, no countersink

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

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Dimensions

sizeM12
P (mm)1.75
s (AF)18
e min20.03
m (height)15
w (unslotted height, as read)10
n slot width (min – max)3.5 – 3.8
ds max (collar, M12+)16
cotter pin d × l (DIN 94, mm)3.2 × 22
slot depth m − w (computed)5
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From the full sheet

Slotted and castle nuts, DIN 935-1, M4–M36: across flats, height, slot width, collar, cotter pin size + envelope models: every size, notes, mating features and sources. What are the dimensions of a DIN 935 castle nut or slotted nut, and what cotter pin does it take?

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