Abstract: An elastic stopper and an enclosure cap incorporating the stopper for sealing a vial while allowing piercing of the stopper. The stopper includes a disk-shaped upper portion and a cylindrical-shaped lower portion defining an interior hollow space. The lower portion is divided into a plurality of longitudinal segments by a plurality of slots. A plurality of longitudinal grooves are provided on the inside surface of the lower portion to break the surface tension between the stopper and the liquid contents of the vial that flow into the hollow space of the cap. The enclosure cap allows multiple piercing without leakage of the vial contents and prevents the vial contents from aspirating out when the stopper is pierced with a single lumen needle.

Abstract: A cassette for supporting a plurality of cylindrically-shaped containers (e.g., test tubes) of randomly varying diameters in spaced parallel relationship includes a frame supporting a plurality of tube centering assemblies in side-by-side relationship. Each tube-centering assembly comprises a housing defining a through opening for receiving a container, and a pair of cooperating collar members slidably mounted on the housing for movement towards and away from each other. Each of the collar members has an arcuate surface adapted to contact a side wall of a received container during the sliding movement thereof. A spring is provided to bias the collar members towards each other and towards engagement with the side wall of a received container, whereby the collar members cooperate in supporting a received container therebetween.