Oops, sorry didn't post picture (typed post while waiting for Photobucket then forgot to go back there).

tub overflow? I think if you remove this plate, the pipe will fall back in the wall. The plate should have been stainless.

Remove the plate, it's a keeper during construction while the tub is set. Once overflow is assembled and attached to trap it wont move enough to lose it

It looks like the flange does not cover the opening in the wall of the tub. If not, with or without the plate, overflow water will go into the wall cavity instead of down the drain. The drain flange must have a watertight seal to the back of the tub wall opening.

I thought the whole purpose of the cover plate was to pull the gasket tight against the drain. I found a diagram on another plumbing forum, says this piece may not be used with all makes and models. Delta website doesn't have it (seems to use a wire and pair of screws instead) on any of their tub wastes. We have all Delta faucets, but have no idea what the wastes are. No manufacturer ID on the back on the cover plate. The modular factory just used whatever they could get cheap I guess. So, what is this piece called so I can look for it in stainless?