Hello. I want to make a fan part for Fritzing. But I want to add a size option (for example 12cmx12cm, 4cmx4cm etc …) to a single part instead of multiple parts. Can you help me please. I made this translation from google translation so it might be broken.
thanks, but ı don’t want it.Iwant a menu like this-> 
That menu should be bottom right of the screen when you click on it, if not there then you need to make custom sizes using the forum I sent.
You still need multiple parts, but if you make the family the same with different variants you can create the menu item in Inspector to select between them. If you post the two parts (a 12CM fan and a 4CM fan) I’ll adjust the fzp file to do what you want and explain how to do it (I don’t think that is in any of the howtos yet. )
edit:
There is in fact a howto that I didn’t remember writing 
https://forum.fritzing.org/t/part-creation-howto-part6-family-and-variant-howto/7917/2
And here are a couple of parts that demonstrate how to do it
fan-2in.fzpz (9.8 KB)
fan-4in.fzpz (9.1 KB)
changing the variant field wil change the fan size like this:
Peter
Thank a lot of you are AWESOME!