Abstract: A valve system designed to regulate the flow of fluids for pressure regulation systems. The valve is defined by a plurality of valve elements in the form of overlapping and interlocking valve blades that can retract and close on command, and defining a central aperture having an adjustable dimension dependent upon the relative positioning of the plurality of valve elements as they are selectively oriented between an open and closed position. The central aperture at least partially defines a free, unobstructed flow path of fluid in pressure regulation applications. The valve system can be driven mechanically or electronically. A mechanical valve control assembly can be comprised of any combination of components that facilitate the operation of said assembly. An electronic control assembly ideally comprises a plurality of sensors each transferring sensor signals to a central processing unit and Shutter Valve driver assembly for purposes of controlling the operation of the pressure regulation system.