What Exactly is a VRT

Sorry if this is a bit of a dumb question but I have no clue what it stands for, also do all officers wear this or only some?

Google is your friend… https://en.wikipedia.org/wiki/Royal_Air_Force_Volunteer_Reserve_(Training_Branch)

Ah yes, thank you very much!

Interesting factoid.

Monday 4th September 1939 all newly commissioned RAF personnel were VR branch. A practice carried on until the war’s end. But by 1942 nobody was wearing the little brass or gilt badges, 'cos they melted them all down to make more spitfires. Or summink like dat.