Flipper Max Magnet Cleaner, 1-Inch Flipper Max can be used on glass or acrylic tanks up to 5/8"- 1" (15-24mm) thickness Patented design that flips from scrubber to scraper. Complete cleaning without ever getting your hands wet! Unique orienting buoyancy for easy retrieval of the cleaner every time. Ultra low profile design allows cleaning in hard to reach areas of the tank. Blades are interchangeable and replaceable