A cap to put onto a CS lens thread. The CS thread is commonly used on CCTV camera lenses.

I drew this model in FreeCAD, feel free to edit the included .FCStd file to suit your need.

Settings I used in FreeCAD to make the CS thread:

Sources:
[1] https://www.e-consystems.com/blog/camera/technology/c-mount-vs-cs-mount-everything-you-should-know-about-these-lens-types/