Creating a 'ghosted' box.

Im trying to make a metal detector and i want to fill the inside of it with a ents.FindInBox but i cant think of a way of doing the offsets?

Does anyone have any clue what the functions that create a sort of “box” are called?
Ive never used them before so i dont have a clue what the function is.

You can draw a mesh quad if thats what you’re asking.

Someone told me the function was obsolete but I haven’t confirmed it.

Thank you, your a life saver.