BROOKLYN INDUSTRIES VEST or is it?

This may be a lightweight sleeveless jacket actually. LMK what you think please! What i do know is that it can be styled in a number of different ways as shown thanks to the adjustable collar cord. Has 2 side pockets with Snap Buttons and love the message inside..little old school, I know. Back Length : approx 25" Medium, Olive Green with some sheen, Grey Lining