Whisper air pump features:Patented dome shape and sound dampening chambers minimize turbulence and produce a smooth quiet stream of air.Wide footprint, rubber feet and suspended pump motor eliminate sound producing vibrations.Thick walls insulate motor noise.Powerful diaphragms provide ample airflow for deep water applications.Single air outlet.Each air pump is covered by a manufacturer's limited two-year warranty. Uses standard-size aquarium air tubing (not included).