What are the product details of double layer roll forming machine?

Sometimes when a customer needs to produce two different metal sheets, siding, trapezoidal sheets, corrugated sheets or metal tiles, a double layer roll forming machine always comes to mind.

Compared with a single layer roof panel roll forming machine, a two layer roll forming machine is designed to produce two different types of metal sheets which can be one for trapezoidal roofing and one for wall/ceiling cladding; 

Or a trapezoidal roofing sheet and a corrugated roofing sheet; or one of trapezoidal sheet metal and one of metal tile; or corrugated sheet and enameled metal tile, etc. In short, two of the metal roof panels can be produced by this same double deck roll forming machine.