Specifically designed for 55 and 75 Gal. glass aquariums. The inside magnet projects 1/2 inch beyond the outer magnet. This extended reach allows cleaning beyond the visible edge of trims and canopies. Other advanced features such as ergonomic grip, replaceable pads for glass, large 2.5 x 3.75 inch cleaning surface set this product apart from all others. This Magnavore product features a one year warranty against defects in materials and workmanship. Product of proved quality at low cost!