British Red Cross Society Cap Badges

[BlueBadger]

I am having a great deal of difficulty identifying the difference between WW1 and WW2 BRCS cap badges. I have also seen references of officer's badges versus other ranks, which I presently have no idea how to discern the difference. I am seeking a nice genuine WW2 officer's badge to go on a hat I recently purchased that is missing the original device. The hat is the early WW2 felt brim hat and has two small vertical slits at the front of the ribbon to attach the badge. I have found several mounting styles online, to include lugs, two single blades (prongs) and two sets of double blades. All very confusing. Can anyone post photos of each style, WW1 and WW2, and identify the differences to assist me in my search. I'm fairly strong on the military items, but BRCS mystifies me at present. Many thanks in advance.

Regards, Jeff