A collapsible chamber metering valve for use in a pressurised dispensing container 2 comprises a generally cylindrical body 3, an elastomeric sleeve 12 coaxially overlaying the body and defining a collapsible chamber 14 therebetween, the body defining an internal chamber 18, channel means 31 providing a fluid flowpath between the internal chamber and the collapsible chamber, an axially slidable valve actuating stem 6 extending coaxially through the internal chamber, outlet valve means 33 operable between the stem and the body at the outer end of the internal chamber so as to dispense fluid therefrom in an open conditiion of the valve and inlet valve means 21 operable between the body and the stem at the inner end of the internal chamber to admit fluid thereto in a closed condition of the valve wherein the inlet valve means comprises an annular seal portion 29 of the sleeve cooperating with an inner end portion 8 of the stem extending therethrough and wherein the sleeve further comprises an annular shoulder portion 16 nestably receiving the inner end 15 of the body, the shoulder portion and the seal portion being integrally formed of relatively thick and thin material respectively whereby the shoulder portion and seal portion are relatively rigid and flexible respectively so as to positively locate the sleeve upon the valve body whilst permitting deformation of the seal portion.
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