Those are structural, on a sub frame car, and have to be cut off, and welded back on.
If your car came with a rocker panel and is no longer present, it's a good idea to buy one. There is usually a rocker panel on most cars. They can protect your car from damage during collisions.
YES
A car has many panels such as a door panel, a header panel, a rocker panel, cowl panel, need more info to answer that Q.
passenger side rocker arm panel
A rocker panel is used in rock concerts and since it has to do with music instruments it should cost about the same as any electric guitar depending upon how good it is and the brand name.
To find out about rocker panel, http://www.autopartsway.ca/Category.cfm?allMk/allY/allmd/allSmd/allEn/allB/Body/Rocker_Panel has all the information you could ever want!
Rocker Panel?
Check inside and around the door or on the rocker panel
at http://www.alfaparts.net/toyotapu.htm
It is on the passenger side beneath the rocker panel.
You MAY be talking about the 'Rocker Panel'.