Army trade S.L.O. ?

Would anyone here be able to tell me which trade S.L.O. might be? I have a paybook for a soldier who judging by his army number enlisted in the Essex Regiment in 1939. He qualified as S.L.O. D.111 in March 42, and relinquished this on transfer to another unit two months later.

Does anyone know what it stands for?

 

Service Liaison Officer ?

 

Good guess, but I doubt it, as he was an infantry private.

 

Could be a "Search Light Operator" - there was a very unofficial and unauthorised badge.

 

This sounds a lot more promising. I checked and two the of Essex Regiment's TA battalions were converted to Royal Artillery Searchlight Regiments (1/6th Essex, and 2/6th Essex were converted to 64th and 65th Searchlight Regiments in 1939).

 

I think you have it there...

 

Looks like it. Thanks for the help.