Juwel Air Diffuser kit turns your pump outlet into a venturi, releasing bubbles and oxygenating the aquarium. The diffusor kit fits all juwel pump heads except the 280 You may wish to add even more air to your aquarium. This is why Juwel have designed the Air Diffuser to blow a stream of bubbles in your aquarium.Simply attach the supplied pieces to the outlet of your pump and you will see an attractive and beneficial flow of air bubbles blowing around your aquarium.These are perfect if you want a silent stream of air bubbles in your aquarium without the need for an additional air pump!