Anemometer Cup and what I call the center dome for the home weather station. The center dome holds the bearing and magnet for triggering the reed switch for measuring wind speed. (Mine is an old Lacrosse Technology from more than ten years ago)
The cups themselves are slightly cone shaped so they can be printed without support. They can be glued to the center dome.
There are two types of center domes; the first one has the dome and collar for the bearing separate, so they can be printed without support. There are two collars, a short and long one. Again just glue them together.
The other dome is all-in-one and will need to be printed with support.
It's lasted over a year through an Australian summer, 45C / 113F days; rain, wind and storms.
(ps: Excuse my spelling of the file names)

Anet

A8

No

No

0.15 or 0.2

100% (Dome 30%)

Print arms and cups 100% fill (solid). Print cups as per the picture.
Dome can be printed with 3 layers (1.2mm) shell and 30% infill.
No need for brim or raft; unless you have warping problems.