Abstract: An elongated aerodynamically shaped fairing is disclosed herein having a body with a passageway at its rear for slideability receiving the bolt rope or cable of a sail and an interconnecting slot with the passageway for conducting a portion of the sail luff exteriorly of the fairing. The body of the fairing being provided with an internal cavity at its mid-section and extending forwardly so as to substantially enclose the length of a sailboat forestay. Pivotally carried within the cavity is a toggle member having a socket for bearing against and rotating about the forestay. Inflatable tubes are disposed on opposite sides of the toggle member and when selectively inflated and deflated, actuate the toggle member to flip to one side or the other of a central plane of the sail at its leading edge.