The Coralife Super Skimmer is hang-on tank mount or sump hook-up protein skimmer for tanks up to 65 gallons.Features:Dimensions: 4.25" X 5.5" X 20.75"Includes Needle-Wheel Water Pump with Air Inlet Silencer Easy-twist collection cupWater-level adjustment dialBubble-production diffuserHigh-grade acrylic construction with custom componentsPatented Needle-Wheel System with aspirating venturiUser Manual (pdf file in new window)