Silence is golden with the Aquatop BREZA Fusion Air Pumps. BREZA Fusion Air Pumps feature a patented baffle system with a series of chambers interlinked by small openings that creates pressure as the air is pushed through each small opening. An easy-to-turn (Models 400-700) air control knob allows you to adjust for precise air flow control. Designed to absorb sound and provide a healthy environment for your fish and aquatic plants to thrive in.