Library › Cameras & lenses › C-mount (1-32 UN): 17.526 mm flange, thread rings; CS-mount

1-32 UN (C-mount) external thread ring section

1-32 UN (C-mount) external thread ring section: ISO 68-1 basic profile, major Ø25.4, pitch Ø24.884, minor Ø24.541, pitch 0.79375; 6.35 long (8 turns), bore Ø20.541 (wall is a design choice); exact nominal, no tolerance

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

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

parameter	thread
value	1-32 UN (2A)
from	standard

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From the full sheet

C-mount (1-32 UN): 17.526 mm flange, thread rings; CS-mount: every size, notes, mating features and sources. What is the C-mount flange focal distance?

Other sizes

1-32 UN (C-mount) internal thread ring section