WW1 Manmoel soldier

[NewRhi]

Hello,
We have found some photos of my great great uncle Thomas Jones (b1892) who was a soldier in the First World War.  I  am trying to find out more about him.  I can't find his service records on Ancestry but I know he and his brother both served in the war.  They were both farmer's sons living in Manmoel, Monmouthshire in 1911.

I have a souvenir card from Germany that says 'From Gunner Jones' and from looking at other websites I believe his uniform is pre-1916 Royal Artillery.  We have two group photos which I think must include his brother as I can't find him there.
I would like to know if anyone can tell me what the initials are in the group photo and if anyone can point me towards more information about Welsh soldiers in WW1(like what regiments they might have belonged to).
Thanks for reading-Rhiannon 

[suzi600]

The cap badge tells us they are Royal Artillery.

The sign tells us the battery .

But this one I cannot make out .

Someone with better sight will come along and work that one out

[NewRhi]

Thank you for confirming that, from the original photo I can see the board says No1 Battery, 4th Section but I can't read the larger initials

[newburychap]

The large initials are R G A - Royal Garrison Artillery

[NewRhi]

thank you