Get down to poundland 99pstore
by a sheet with all them watch batteries on there.....
just above the mount rail there is compartment - shove in 2 cells
(well open it up and see if there are any dead ones in there - but most likely 2 x 1.5v)
EDIT - Mack is correct - I f*cked up in this post it is NOT AG13 - these went in my Eotech
I used AG3's in the ACOG - way too small diameter wise but did the job to test it out
my bad for saying you need AG13's - they will never fit in there - just checked
Correct battery is L936 / LR45 / 394A / AG9 - cheers Mack
for what its worth here is a chart with info on sizes/codes/different numbers etc.....
Seems like me using AG3 is 7.9mm diameter instead of 9.5mm diameter - same thickness 3.6mm but smaller capacity
So seems like I should also order up some L936 / LR45 / 394A / AG9's
Thanks to Mack - soz for me talking out of my duck's ar$e once again - my bad