How would i create a plastic film around an object? I know i need to use the offset srf command, but how do i detach that srf so i can add diffrent material to it?

I have a cylinder, how do i create a plastic film around it, so its like offet surface but i want the surface to be detached so i can give it a diffrent material

If you select Solid = No, it should be detached. No?

ahh ok thanks