The DC 3900 Twin is a portable but very powerful dust extractor suitable for large quantities of dust due to its integrated pre-separator. It is particularly suitable for concrete grinding since 80–90% of the coarse materials are separated in the pre-separator. The remaining dust goes into the filter cyclone. The DC 3900 Twin is a flexible machine since it is powerful enough for most applications yet it can be easily moved and transported. The air flow capacity is suitable for concrete floor grinding machines with diamond discs of up to 500 mm/20” diameter.