As a translucent primer coating the stuff was applied during many different stages of an aircraft's production, at the main factories and among the many smaller subcontractors that were employed to manufacture parts. A piece of aluminum stock would be stamped, then coated with a layer of Aotake to prevent flash corrosion. Then that part would be drilled and cut, then given another coat of Aotake. After that part was riveted into place within the air frame it would be coated a third time or more. The procedure was generally to ensure that no bare metal was exposed to the air for any length of time. Then, in some areas of the aircraft, a matte black coat of paint was often applied - as a further measure of protection or to cut down on the glare of the glossy Aotake, it's not known. It's generally accepted that there were two main variations of Aotake: a blue and a green (though other shades including yellow have been encountered). Some have suggested a number of different means to predict the application of either variant - time frame, manufacturer, or other. In reality both blue and green could be expected to be seen in any random aircraft regardless of manufacturer or time frame