Abstract: A cap member for a window stay, particularly a four bar friction linkage stay, comprises a recess for receiving the tapered end of the bar which is attached to the openable vent of the window when the window is closed, and a pivotally mounted pawl member having a surface which defines an internal cam surface of the recess and which is adapted to engage and guide the tip of the bar as the window is closed and the tapered end enters the recess, the pawl pivoting so that when the tapered end is fully received in the recess the engagement between the tip of the bar and the inner edge of the pawl causes the outer edge of the pawl to bear against the inclined edge of the tapered end to hold the bar, and hence the window vent, firmly in the closed position.