What exactly is a Trailer Hitch Cover? - Stupid question I know...
 

My dad has a Truck with a Trailer Hitch on it. With a standard "ball" ? standard 2" I believe.. He uses it to tow his boat...

But his hitch is getting a little rusted so I wanted to buy him a hitch cover....
but i'm effing stupid and don't understand how these things work??

will this work on my dad's truck?
ebay listing link here

^ this one doesn't look like it covers it at all.. it looks like you have to take out the ball and replace it with this.. am i correct in saying this?

Thanks..

Yeah, correct...

That thing covers the square hole in the following picture:

http://www.suspensionconnection.com/...itch_large.jpg