Abstract: A pressure equalizing liquid addition funnel for a closed system reactor is described. The funnel includes an internal valve stem which seats in the outlet port and extends therethrough and which defines a lumen which extends axially from below the outlet port upwardly to a port in the valve stem in the upper portion of said flask. The valve stem then terminates in a valve cap which is threadedly mounted on the funnel whereby rotation of the cap will cause the valve to engage or disengage a valve seat at the outlet.

Abstract: This disclosure describes a quick opening valve structure particularly suitable for use in laboratory applications as a stopcock and the like. The structure includes a valve housing, which may be made of glass, and has a barrel section defining a valve chamber and coaxial inlet and outlet branches leading to and from the chamber through respective inlet and outlet ports. The axis of the valve chamber is disposed at an acute angle to the common axis of the ports. A valve plug, which may be made of a polymeric material, threads into and out of the valve chamber. The plug has an inclined end face disposed at an angle corresponding to the angle of the valve chamber relative to the axis of the ports. The plug has a closed position isolating one port from the other. Rotation of the plug 180.degree. from the closed position in a direction threading the plug outwardly of the chamber, provides substantially full opening of the valve, with the end face of the plug disposed in parallel to the common axis of the ports.