All you have to do is immerse the "abrasive" half in the water, make the other half stick to the outside and guide the magnet from the outside by making light circular movements on the glass of the aquarium.
The protruding edge makes it possible to clean even hard-to-reach places, e.g. ex. behind the technical equipment of the aquarium. Guiding through the angles is quite possible without any contact with water.
Thanks to the patented JBL edges, the silicone seals of the aquarium are protected by the bevelled edges. The floating interior element cannot fall into the chippings at the bottom of the aquarium and scratch the glass with stuck chippings. On the other hand, there is no need to immerse your hands in water if the magnet comes off.
For glass: <6 mm
For glass: <10 mm
For glass: <15 mm