Abstract: A valve for a pressurized dispenser which includes within a mounting cup, a valve housing and an annular gasket for sealing a discharge passage of a movable valve stem, the gasket having peripheral edge portions which do not extend to contact the valve cup surrounding wall, and a marginal portion between its peripheral edge and the portion clamped between the mounting cup and the valve housing, and which incorporates a clearance space within the cup and beyond the periphery of the gasket to accommodate the marginal portion of the gasket when stretched during the filling of the dispenser so that a flow path is provided to the outside of the housing. The gasket is preferably polygonal in shape, for example hexagonal.