I purchased this to wear underneath a Fjallraven Kiruna parka when I need the extra heat. I am pleasantly surprised at how much heat this vest retains, yet, remains thin enough that my jacket is not uncomfortably bulky. In fact, I LIKE how my jacket looks with it on: the added girth slightly rounds out the jacket well and actually wears on me better since the jacket is a little long on me. Plus, it’s very packable—it can be tightly rolled or folded into a backpack for traveling and won’t take a whole lot of room.It’s surprisingly well-made, given its reasonable price point: it is a lightweight fill, but I believe it’s made with down. It only has 2, small snap-outer pockets but as the intention is to wear it underneath a jacket, it’s more like additional, inner security pockets for me. As a layer to add warmth to a jacket, I’d easily buy this over a much pricier Fjallraven vest—and nobody will know the difference.I will admit, I’m surprised it didn’t fit better, given the specialty size. I am 4’11, 105 lbs (on a good day, lol), so given it’s a Petitie XS, I thought it would be more fitting: I was surprised it fit as if it were just a regular XS, not only because it still felt loose (more like what I’d expect from a Small, even) but more importantly, the length extended well past my hips: the “Petite Standard” was probably based on the taller end of the short spectrum at 5’3. I guess it’s not so bad since the extra length will help with coverage. And if I’m being honest, I like how the fit isn’t too tight and very comfortable—and it actually doesn’t look too bad without the jacket!?