The Groschenbox is a useful little gimmick that makes life easier on the road. Known from DM times they know many and among taxi drivers she had always been popular. Even people with visual impairment often use these parts. One can also very fast count amounts appropriately because you do not have root only in small change and yet not find the right coin.
I bought two, first euro coins are much heavier than the Mark and make holes in your pocket and purse, so I'll take my change anyway from the circuit and bring it every 6 months time to the bank, a Groschenbox Tucked away in the car , the other is equipped home. Excess coins end up in the money box, issued to replace quickly.
Not what one would absolutely need, but who has become accustomed to a first geordenten cash reserve which no longer want to do without him.