This product is the Blue Matala Filter Pad for the Medium Aquafalls. Blue is a medium density pad used for small particulate removal. This Medium AquaFalls Pad is shaped like a trapezoid, measuring 23.5" long on one end, 20.5" long on the other and 30" wide. 3 pads per Aquafalls are required. You can mix Green, Blue and Gray for best filtration results, but have the water go through the coarsest pad first.