I am tired of uggly antennas sticking out of streaming products. Especially when the antennas are not being used. But I don’t want to leave the connectors exposed to dust or other kinds of interference.
I have found various options of dust caps for RCA, RJ45, XLR etc etc. But nothing clear cut for unused wi-fi antennas ports? 
Please share with me products that you are using or ideas?
I found these on amazon:
Router Antenna Protective Cover Dust Cap for TNC Female Connector Adapter
here is the link: Amazon.com
There are several different types available. Some with retention chains, too.
Really depends on what connection your device has…
Thank you very much! 
May I ask what retention chain is? I mean what is the use of it?
For standard 2,4/5ghz router or streamer applications, I guess standard is fine?
So the cap can be attached to the device to not get lost when undone.
But there actually isn’t any need for protection against dust or other interference unless you’ve got frayed cable ends behind your components threatening to cause short circuits, which seems unlikely given your request for help.
Like @Marin_Weigel said dust caps aren’t really needed unless you are in a VERY dusty environment (dirt floored barn for instance) or outdoors where critters (spiders etc.) can get into the connectors.
BWT, Retention chain looks like this (there are various styles):
