Technical reports are warning owners not to peel a protective layer on the iPhone Duo's inner screen.

The inner display has a nano-texture finish meant to cut glare and reflection.

It can look like a temporary plastic film, but it is part of the screen.

Peeling that layer permanently ruins the display, the article says.

The outer material is described as a replaceable cover, separate from the nano-texture.

The display is also engineered to reduce the central fold crease.

A replaceable inner cover is meant to handle wear so technicians can service it without replacing the whole display.

The article says that cover work has to be done by authorized service centers.

Read the full article on the iPhone Duo nano-texture layer and why it should stay on.