After an "adjustment" very useful tool

I ordered the brush on Amazon. Delivery time went even faster. To brush itself:

The bristles are nicely taut to achieve coarser dirt that a toothbrush can not abkriegt and is also more deeply into the cassette.
When I tried, it was too thick to fit in my 10 XT cassette. After fifteen minutes, everything went perfectly.
Did they just made little "thin" with a utility knife and sandpaper. Should be used cautiously !!! But it works.
The dirt remains wonderfully attached to the teeth. Simply hang the bike on the stand, the brush with the prongs between the sprockets press (bristle side as a handle) and the crank move forward. Even the thick seed is intervening on the brush. These can also be washed easily. Finally, with the long bristles and the cleaner fine dirt out brush. Done. Perfectionist like me then polish the cassette still bright with the toothbrush. The longer holds the pinion Chain team.

Conclusion:
Not complain about this brush. Sometimes you have to just come up with something rather than moan equal.
Fits in 7 Series / 8-cassette purely easily! From a cassette 9s a post is necessary. With a little craftsmanship but zero problem.

For almost 6 Euro no wonder device. But does the job to clean the cartridge. More does not have to.