Aussiespeed Holden grey motor dress up and header package includes AS0138 Australian made cast iron dual outlet headers, alloy rocker cover and aluminum side plate. These are available in various surface finishes. You are purchasing a polished aluminum 3 fin rocker cover AS0121P-3 and cast aluminum side plate AS0101P.
The rocker cover uses factory steel oil filler cap. The side plate can require the holes slotted if the engine block or cylinder head have been machined.
The cast iron dual outlet headers are supplied with steel flanges, flange gaskets and studs with brass nuts.