What's a perch on LCAs?

[lietuvis91]

this may be a dumb question, but i am going to install some new springs on my car and thought that i should install some new LCAs while I'm at it. So in trying to decide what to buy i realized that I have no idea what a perch is?! Do we need control arms w/ perches or no. I am sure i need the sway bolt up on the lca as our cars have sway bar. Let me know please..

 

[Suspect]

yea u need it. its what the spring sits on.