Abstract: A fluid flow control valve includes a valve body including a side wall, an inlet port through a portion of the side wall, a top, a bottom, a discharge port centrally located in the bottom, and an interior chamber; a piston slideably mounted within the interior chamber, the piston having one end overlappingly opposing the concentric with the discharge port, the one end having a centrally located recessed portion; a sealing member removably secured to, located within, the concentric with the recessed portion of the one end of the piston for providing a fluid tight seal between the piston and a valve seat about the circumference of the discharge port whenever the piston is positioned for closure of the valve; a throttle rigidly attached to and concentric with a portion of the sealing member, the upper portion of the throttle proximate the piston being cylindrical and having an outside diameter approaching the inside diameter of the discharge port, the lower portion of the throttle including a plurality of scallo