The filter is automatically cleaned every 15 seconds reducing filter clogging and delivering constant airflow A filter is automatically cleaned every 30 seconds reducing filter clogging and delivering constant air flow Automatic start and stop control when the power tool is operated. The machine continues to run for an extra 15 seconds to allow all dust to be cleared from system Innovative dual filter cleaning system maintains performance during tough construction applications The DeWalt DWV902M M-Classified Dust Extractor has an innovative dual filter cleaning system that maintains performance during even the toughest construction applications. It ensures constant suction power, even with the finest concrete and wood dust. Each filter is automatically cleaned every 15 seconds, reducing filter clogging and delivering constant air flow. An audible alarm alerts the user if a drop in performance occurs.

On/off switch to stop the automatic filter cleaning if required. Reset function automatically activates the automatic cleaning system for the next switch on.