The converter clutch system on Allen Engineering’s SP425 series trowel provides torque for floating with pans and finishing. Standard features include power or manual steering, the choice of a 34-horsepower liquid-cooled gasoline or turbo diesel Vanguard engine, and two 46-inch diameter, 5-blade non-overlapping rotors with speeds of up to 165 rpm. Other features include heavy-duty gearboxes, a driveline with an electric-powered spray system for retardant application, a flip-up seat and removable screens for engine, clutch and drive-line accessibility.