The power plant behind the system is a Tri-Lobe blower vacuum powered by a Honda petrol motor. With the correct air flow calcualtions and matching the petrol motor to the RPM requirements of the blower a massive suction is created which when matched to the three stage filtration, sets up the Vac N Sack system and its inter-dependant characteristics. Simply put, it is a jigsaw puzzle to get the right flow, suction, vacuum rating, sack porosity and hose response.