Perhaps the worst glass brush I have used since 1980.
The interior is EMPTY, and the brush is only 7-8 centimeters long on the rim, and there is only a small brush ball at the top of the central part. In other words, it takes longer to clean a glass than if it were done with a traditional sponge.
As for the quality of construction, it is not only dangerous, but also tear-inducing. Either it will fall apart (without hot water), or you will get your hand caught in the wires that hold the perimeter bristles.