Photo is reversed,,prop is going wrong way
Likewise Brevet on 2nd left.
They all appear to be wearing the 1941 Pattern Mae West, which should have the oral inflation tube on the left breast. However, I have no idea when the '1941 Pattern' actually began replacing the '1932 Pattern.'
LFH
Edit - Disregard - Not 1941 Pattern after all. See GeeRam's post below
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