Obviously not a Gents product but as Gents didn’t make their own accumulators then I have no choice but to show another make.
These are exactly the same type that would be used in a typical system . This is only a bank of 3 but normally there would be quite a few more. These have never been used and I have been advised they would,come dry charged and the correct amount of acid added on site. I have had a few different options on these and no one can date them exactly. Probably from the 1930s-40s.These have a custom box made for them in the past .I will never use them as if I do they will only deteriorate with age 
. Never the less a rare find and nice display item Andy