Does a milage accumulator exist on a MB!!

[kayooh]

Hello List,
Please tell me whether or not the following is true.

I have come across a 1992 600 SEL that is in immaculate condition with very low mileage (The car is in Europe).
As I was discussing with the owner that such mileage maybe due to a replaced odometer, he assured me it was not and that I can double check true mileage by taping into a mileage accumulator of some sort which resides somewhere in the vehicle!!

As far as I know, this is very hard to believe but still doable.

Does such a thing exist or is he BS'ing me.

Thank you all.