The MCB unit creates a cross draft ventilation that eliminates hazardous contaminants before recirculating clean air. It prevents fine dust from migrating to areas with sensitive electrical and mechanical equipment. There are no obstructions from source capture devices, worker can perform their job with the need for fume arms, hoods or other barriers that can innterfere with manufacturing operations and parts movement. The units come in 3ft, 6ft and 9ft sections and can be combined to create any width and CFM combination in 3 ft increments. After filters can be added for improved air quality. Preconfigured single and multiple unit packages provding 4,000 to 38,000 CFM. Higher CFM applications achieved through combining multi-unit packages.