Eurovent offers a full family of airfoil and backwardly curved fan designs with overlapping performance envelopes. To maintain high efficiency and maximum economy, the system's pressure and flow requirements are matched to one of eleven wheel designs with varying rotor widths and diameters. The selected fan is then sized to exact duty requirements. No more, no less. Wheels are available with either Eurovent's proven hollow airfoil blades for clean air, or solid backward curved or backward inclined blades for dusty, dirt applications. With eleven rotor designs, custom sizing and duty matching blades.