https://help.altair.com/feko/topics/feko/getting_started_guide/GS6_waveguide_divider/waveguide_divider_union_last_feko_t-example6.htm
Unioning the Waveguide and Power Dividing Pin
Create a single geometry part from the waveguide and power divider pin to ensure mesh connectivity when the model is meshed.
unioningwaveguidepowerdividingpin