What is a tailgate band made out of?

[Chevy3+3]

Thanks for the replies. I did figure out that with a very thin coating of wd40 or other similar lubricant that it takes away the foggy look and brings the shine back. I will probably just continue to do this as needed for now.

If I ever repaint the truck then I will probably remove anodized coating and polish all the pieces of trim. My band looks pretty good right now. I could polish it now but I dont want the highlight of my truck to be the aluminum tailgate band, lol. Its a used truck so a tailgate band that looks a little used will fit perfectly.