What are "ACCUMULATORS" for MB suspension systems.

What is your question?

After stupidly leaving a very heavy load on my '94 E-320 Wagon, my MB sits lower and driving bumpy roads feels like I have no shocks. I depressed them for so long that they are no longer absorbing bumps as they should -- or so I thought.! I was simply going to get 4 new shocks since the coil springs are O.K. My MB mechanics say my shocks are O.K., and all I need are a set of "ACCUMULATORS" for a mere $700 +. I do not know what they are yet, but I am confused now. Can anyone educate me about what they are talking about? Thank you very much, CARL ERLENDSON ---------