I didn't do it. It is on the original base plate. I'll bet it is a factory spraying, but someone left something on the surface. If you want to copy that, use a can of paint or a piece of cardboard as template and then spray over it.
Hell, it's must have been like 100 years... Anyway, I never forget a project. I managed to convert this: On this: It solves my problem with HDDs since that blank PCI card it's a 2x 2.5"HDD PCI tray now. I liked it so much, that I planning using another one in other project. I promise to upload a "in action" shot very soon.
