I believe this to be an earlier Alpha Jacket.  Not sure as there is no alpha branding stamped on the interior like the exposed button Alpha that has Polartec Alpha marked on the interior.  Style is 1178. Insulation and lining both poly.  Below is description for the Alpha, same cut as this, but as I said unsure of insulation type.  Sizing shown in pictures. Pretty generous for a small at 41 inch chest and longer sleeves.

Alpha series combines high tech Alpha insulation

with a vest or snap jacket. Originating from the military as a

breathable insulation technology, Alpha insulation is said to be

excellent for physical activity and claims to prevent the user from

having to shed or add layers.$350 jacket features Alpha 80 hydrophobic insulation on the front of the jacket

and lighter Alpha 60 on the back and sleeves along with a C6 DWR

treatment for water repellency. Updates to the jacket include a new snug

fit ribbed cuff for improved insulation of the arms and improved fit.