EasyPro Pro-Series Pond SkimmersThe Pro Series skimmer kits come with black silicone sealant. The innovative design allows you to choose between a vertical filter mat or filter brushes. The two chamber design eliminates cutter filter pads to fit around the pump and it's plumbing. These pumps can be inspected or removed without moving mesh net or filter pads. The Skimmers have a flange above the opening where water enters from the pond into the skimmer. You are able to stack rocks