Transfer device valve

There is disclosed herein a valve comprising: a housing having a first opening, a second opening and an interior wall; and an elastomeric member positioned in the housing. The elastomeric member comprises a continuous peripheral wall projecting from a surface, and a slit extending through the surface. A continuous portion of the peripheral wall creates a continuous sealable contact with the interior wall of the housing and partitions the housing into an upper section and a lower section. The elastomeric member is configured such that upon creating a pressure differential between the upper section and the lower section of the housing: upon infusion of a fluid through the first opening, the peripheral wall is deflected from the interior wall of the housing to create a fluid passage around the elastomeric member; and upon aspiration of a fluid through the second opening, the slit opens, permitting fluid flow through the elastomeric member. The interior wall comprises at least one recessed channel therein and extends substantially along the longitudinal axis of the housing. Deflection of the peripheral wall from the housing substantially corresponds to the placement of the at least one recessed channel.