Mile High Mountaineering Flatiron 42 Backpack. Discontinued pack from a revered American manufacturer.
Used for one overnight and one day hike only. Two small stains (see pics), but otherwise it's pristine. I like it fine, but I've got one pack too many...
Would make a great backpacking pack, or a cragging pack thanks to the full side zip and rope strap on the top. It can be a sleek 42 liters, but with the top extended, I'd say it can comfortably carry 50L+. The brain unclips easily and makes a surprisingly useful day pack.
For alpine pursuits, it's bomber, close to waterproof, most of its bits are strippable or stashable, and it has ice axe loops too.

Bought new for 200 in 2019, asking 90$ + shipping

Good rundown of features here:
https://www.youtube.com/watch?v=3TXFiXB2gtc
https://blisterreview.com/gear-reviews/mhm-flatiron-42

Small stains in out of the way places. In the mesh back panel inside:

On the side stretch pocket: