Abstract: A two-piece valve including a first tubular member having a flow passageway therethrough with a tapered valve seat formed at one end of the flow passageway. A second tubular member is provided having a flow passageway therethrough and a valve element mounted in the flow passageway on the axis thereof. The first and second tubular members are slidably telescopically engaged with each other with one end of the first tubular member slidably positioned inside one end of the second tubular member. The valve element of said second tubular member has a tapered valve surface formed thereon adapted to move into and out of sealing engagement with the tapered valve seat of the first tubular member when the tubular members are telescoped axially one inside the other. The taper angles of the valve element and seat are in the "self-holding" category so that when the valve element is firmly seated in the valve seat the parts will be retained in mating engagement without any additional retaining means.