This is a used Marmot Reactor Fleece vest - purchased from Amazon and only worn a few times. Has been in a cupboard ever since. Pit to pit measurement is 18.5 to 19 inch (see photos).

Here is the manufacturer info:

About this Item

Full front zip with chin protection

Front zip with chin guard, two side pockets with zip

Drawcord At Hem

Polartec Classic 100Micro; flatlock seam construction

Made from Polartec Classic fabric, the Reactor Vests offers a light-weight extra layer of plush warmth and breathability either on its own or layered with your favorite Marmot jacket. Description Product Description Made from Polartec Classic fabric, the Reactor Vests offers a light-weight extra layer of plush warmth and breathability either on its own or layered with your favourite Marmot jacket.