Suspension Bar ?

[Talies R]

Don't mind my noob question, but what kind of bar is it that I keep seeing underneath cars, it's usually shiny? :dunno:

[Rsxstacy]

Lower tie bar

[Ben]

Tie bars in the front, Lower sway bars. generally measures in millimeters diameter.

[my-donair-tc]

Tie bars are usually in the rear...