Nilfisk Meteor vacuum cleaner dust container cyclone insert. This goes in the dust container to use the cyclone effect to separate the dust into the dust container and allow free passage of the air. It helps to protect the foam Pre-Filter and the H12 HEPA filter behind it.
At the moment, standard postage is capped at a maximum of $25 within Australia, so maximise the saving on postage and buy something in the related parts below!