These rear wheels come in a pack of 2 and fit the RED Nilfisk 2200Watt Combat bagless vacuum cleaner.
AS OF JANUARY 2015 THESE WHEELS ARE NOW OBSOLETE AND NO LONGER AVAILABLE FROM NILFISK.
Just a push on fit, but take care when taking off, carefully push a large flat bladed screwdriver between the wheel and body, from the underside/back quarter direction. The wheel is held on by the 4 "springy" teeth on the inner (black side) of the wheel, on the right hand side of the picture.
As this product is now OBSOLETE, Andy suggests it be replaced by the excellent HEPA Filtered VP300, see it, by clicking HERE and buy it with FREE FREIGHT !
We're commercial and industrial dealers and only recommend EXCELLENT machines.