Yes aluminum. I took it to work and cleaned it pretty good. I wasn't looking specifically for cracks, but if something looked strange I'm sure I would've seen it.
I have one sitting in the back seat. They're oem magnum bolts w/ their washers. In the video you can see the bottom of the bolt sticking through.
Just remembered that I saved the old gaskets, here's pictures. There's indention's at the bottom where it sealed:
View attachment 1715371463 View attachment 1715371464
I though I was in focus better, I can grab better pictures in better light if I need to
