cutting tool or machine?
Looks like a face mill with the head out of tram.
It's a shaper. There are slight parallel lines running the long direction of the part. Not a bad finish but much more can be done.
7075-T6 will produce mirror finishes with the right tooling. It's very hard, about 20% harder than mild steel. It's the one type of aluminum where the swarf cuts you.
Shapers can produce some interesting finishes.
Here are some examples on steel:
This first is the finish from a regular finish cut in mild steel.
Next we have some fancier finishes.
Amazing finish on those parts Evan, how did you get them so white you cannot even see them on the screen???
Must be your new internet filter system in operation. They show up fine here.
I cleared the cache but still nothing shows..The filter must have classified it as pr0n..
Try this. I made one change that might disclose how the filter works.
I'd say a slab mill on a horizontal milling machine.
Since Dan is the proud new owner of a US Machines vertical mill, I would guess that is what he used to produce that finish. A properly trammed vertical mill with a sharp cutter is quite capable of producing a very nice finish.
If I had to guess which specific cutter he used, I would go with either a fly cutter or face mill.