When Australia entered the war in the Pacific, soldiers required a drastic change from their heavy wool uniforms and steel helmets.
Uniforms in heavy-duty, but light weight cotton were introduced, including the Jungle Beret.

D arrow D stamped
Manufacturer Stamp V445
Size Stamp unreadable but looks like 7 - 1/8 (so pre 1966)

Size S/M is adjustable from ~54cm to ~57cm

Please note: as these are military surplus there may be some colour, quality and style variation to the image shown.