Abstract: For use with a test tube having a circular-cylindrical wall defining a mouth and having inside and outside surfaces, there is provided a cap of larger diameter than the tube and having a plug adapted to extend into the mouth with interference fit with the inside surface of the test tube. A sleeve on the cap extends along and spaced from the outside surface of the test tube. The sleeve has a greater length than the plug, so that the sleeve still surrounds the test tube wall after the plug has been pulled from the test tube mouth.

Abstract: A device for removing a cap from a test tube under sanitary conditions has an enclosure receiving at least part of the test tube and cap and isolating them from the atmosphere. A plunger reciprocable in a cylinder sealed to the enclosure can be hand operated to close normally spread gripper members against the cap flange and to pull the so-gripped cap from the tube. Any discharge from the just-opened tube is confined within the enclosure. The uncapped tube can be removed from the enclosure, and the cap also can be removed for reuse.