Impact filter cleaning mechanism - Turn the dial to impact the filter case releasing the dust from the filter. HEPA filtration system - Captures 99.97% of concrete dust particulates 0.3 microns and larger. Adjustable depth stop - with 5mm increments. DX Extractors - Powered by a separate motor allowing the rotary hammer to maintain peak drilling performance. Single stage dust extraction nozzle to suit 4 different length drill bits from 110mm to 165mm.