Following advice I ordered an XL. I wear 42 or 44 Battledress depending on layers and the XL is a good fit. Certainly large enough but not clownish. Already wore it as a raincoat and it does the job although having a hood would make it better.
Another winner!

Ed - Virginia United States

Fast shipping , great quality repro!! A++++

Asier - ES

Jerry does it again. Superb well made hard to find item. Thanks WPG.

Harte - UK