The M10 by Patagonia is one of the highest rated shells out there… Its plenty durable, very water proof, insanely light, reasonably breathable, and very packable. This is a 2016 version, which is the lighter model.  It was prior to them adding pit zippers and hand warmer pockets, so it’s about 1.5oz lighter than the newer ones.  Around 8oz for this one…

It’s a size XS, but much more generous than most XS Patagonia stuff. I wear a Small in 99% of my Patagonia kit for a reference, and yet I can layer this over a size small R1, puffy vest, or micro puff jacket easily.  Only flaws worth mentioning are a bit of discoloration/dirt on the cuff closures, but no holes or tears anywhere.

Retailed at $329 when I purchased it, and new versions are at $400…
$160 Shipped CONUS