Description Strong Magnet: This magnetic aquarium cleaner has built-in double magnet. As you move this magnetic aquarium brush, when you move the small outer aquarium brush, the magnetic brush inside follows: Quickly and easily cleans away algae growth to keep your aquarium healthy and looking its best. Anti-slip handle: The upgraded soft grip is contoured, anti-slip, comfortable, saving time and money. Note: Not suitable for acrylic aquariums and low iron glass aquariums Removes algae and won't damage glass: The side of the scrubbing handle is covered with felt so it glides easily when you move it, the other side is made of fabric with tiny hooks that scrape algae algae without damaging the glass. Floating Design: This magnetic glass cleaner inside the brush won't sink to the farthest depths of the aquarium. Convenient to use. Size: S (8 x 3.6 x 6 cm) glass thickness (less than 4 mm)