Fit is more tanker or bomber style. Softshell material. Attachment points for the outer jacket.
Feels good, not terribly bulky, roomy cut.

Think i'll need to buy the jacket too.

This is a fully functional and premium quality jacket by itself and Kitanica has made it right here in the U.S.A. from American stuff. As a stand-alone jacket it's warm enough with a base layer, versatile and comfortable. It protects reasonably well against wind and does fine with a light drizzle. Overall, it's softer and less bulky than the Mark I itself, which is entirely as expected.
The fit is better than the Mark I and that's mostly because of the neater, tighter construction; obvious considering it was made to fit inside the shell. The waist is still a little on the tight side, but it's not much of a problem because it doesn't bunch up like the Mark I and it's more flexible. The sleeves are shorter than the shell, but not at all too short. The fit about the chest and shoulders is excellent on my frame.
The pockets are more useful and convenient than on the Mark I. Part of that is down to the more compliant fabric, but also ergonomic placement and the mobility of the jacket itself. The zippered handwarmer pockets open to large, interior pockets zippered at the top on the inside. The interior pockets are a finer, softer net than on the Mark I and I'd still prefer a sturdier fabric. The exterior breast pockets have generous pull tabs so access is easy; they're flat but large enough for a wallet or normal smart phone or similar. The pen tubes are easier to get to than those on the shell, owing to the softer fabric.
I have two complaints: the mounting loops that secure the liner to the coat are unsightly, but this can't be avoided and I don't care that much. If I were buying this alone and never intended to buy the shell, I would carefully snip off those liner mounts. Second complaint: I wish it had a 2 way zipper.

I've only had this jacket for a week or two, and already it's become my preferred "go-to" whenever I leave the house. The quality of the materials is superb, and the materials feel very robust. The layout of the pockets is logical and offers plenty of storage. The zipper is heavy duty and moves smoothly and rapidly.

This jacket does have a cut-off that ends at my waist, so it "feels" short, but it's tactical and practical and gives easy access to my pant pockets. However, I do have to be attentive when wearing layers so that my t-shirt or button-down shirt isn't draping out from the bottom. That is aesthetics-based, just know it's a bit shorter than a regular jacket.

Additionally, given the material of the jacket, and the way it wears, it can seem loud and noisy as you move your arms. Taking a walk around a quiet neighborhood, you'll hear the sound of the material friction-rubbing against itself. Put your hands in your pocket and the fabric won't move as much and thus quieter. This is not a dealbreaker, just something to note.

Overall, I am elated with this jacket. The fit and finish is splendid, and for an extra large body-type like mine, I'm glad their sizing can accommodate. I took a chance on this jacket, and I do not regret it. Just be mindful that you might feel like your local bad-**** every time you put this thing on.