Royal Field Artillery
One of 4 branches of the Royal Artillery between the period 1899 to 1924.
The others were the Royal Horse Artillery, the Royal Garrison Artillery and a group just called "The Royal Artillery" which looked after ammo supply and so forth.
The RFA used the lighter guns such as the 18 pdr and 4.5" howitzer, and wore the collar title "RFA".
More to follow.