NilfiskCFM industrial vacuum cleaner 70mm to 40mm steel reducer for hoses.

This usually fits in the 70mm container inlet of and the and the  and the  so they can use the 40mm internal diameter  hoses.

In the picture, it's similar to the part seen coming out of the container and the 40mm hose is connected to it via a PVC or rubber 40mm cuff.

At the moment standard postage within Australia, is capped at a maximum of $30 so maximise the saving on postage and buy something in related items below!