The MAPfrac® ball activated Frac Sleeve is designed for use in multi-stage fracturing operations within a horizontal wellbore. Generally placed at equal distance and isolated between stages, this robust design allows for effective proppant placement in the wellbore through a series of exit ports. When RIH the valve is closed and is not affected by differential casing pressure until the ball has seated. By using specially sized frac balls each valve is shifted open in a set sequence that allows communication between the formation and casing. By performing individual staged fracs, a continuous operation can then be maintained.