Ram/piston

Hi my RR has a 2inch lift and i am just wondering what the big ram/piston thing that is attached at one end to a cross member and at the other to part of the A frame as far as i know it is something to do with self leveling i think.
Can anyone tell me if that is correct and if not whats it for thanks

it is self levelling unit ,you can remove it and fit stronger springs

Ok thanks think I will do that but as im not sure what springs are in it as it was lifted before I got it what would be stronger springs?

see how it sits , it may well be ok with whats fitted