Nilfisk and Tellus GS80 and GM80 and the Nilfisk GM90 and GS90 commercial vacuum cleaner motor replacement microfilter to protect the motor bearings etc from fine dust. It fits like a sock over the motor, reducing filter particle size to 4 microns.
They also are for the Nilfisk and Tellus GA71 GS81 and GM81 industrial vacuum cleaner as well as the GM82 and Nilfisk GS83 and GM83 and the Nilfisk GM 625 etc. In the past there have been several other part numbers for this item, including Pn. 61682100 and Pn. 62348710