[Super Magnetic Force] The magnet part of the magnetic brush is NdFeB, so the magnetic force is stronger than ordinary models, and can be effectively adsorbed on the glass of the fish tank without falling off. Note: Due to the strong suction force, it cannot be forcibly opened. Just rotate the upper part of the magnetic brush 90 degrees to open it. The M Size is suitable for glass thickness of 0.23", large size is suitable for glass thickness of 0.25"~0.36", and the extra large size is suitable for glass thickness of 0.25"~0.62".[2 in 1 Function] The magnetic brush combines the scrubber and scraper into 2 to 1, which can effectively clean the glass and easily clean stubborn traces even around the corners.[Self-Floating Design] The magnetic brush will not sink to the bottom of the aquarium when it is separated, it will float, so you can easily retrieve it without getting your hands wet or disturbing the fish. When not in use, it can be directly attached to the glass without additional storage.[Comfortable Grip] The overall design of the magnetic brush imitates tactile engineering, adapts to most hand holding spaces, and has a good operating and grip feeling. 3 Multiple size options: Medium: 10*4*5cm, Large: 12.5*5.5*5.8cm, Extra Large: 14.5*6.3*6.5cm.[Wide Applicability] The magnetic brush can be used not only to clean the aquarium, but also to clean the window glass. Supports saltwater or freshwater aquariums.It'll be a nice father's day gift for your daddy.