Abstract: A test tube stopper (1) has the shape of a small bowl and is provided with a protruding upper circular collar (11). The stopper (1) slidably enters into and seals the neck of a test tube (3) until the collar (11) rests against the mouth of the test tube (3). A horizontal bottom wall (12) of the stopper (1) is comprised of two or more elastically yielding sectors (16) which can bend under the action of a device (43) being introduced into the test tube (3) through the bottom wall (12) for introducing or withdrawing liquid. The resilient sectors (16) return to their initial position as soon as the device (43) has been extracted from the test tube (3) through the bottom wall (12). In a preferred embodiment a stopper (2), preferably of the conventional type, sealingly closes a cavity (14) of the stopper (1) to ensure sealing a vacuum previously provided in the test tube (3). The stopper (2) may then be removed when it is necessary to withdraw blood from the test tube (3).

Abstract: A safety closing device for containers of biological liquids and, particularly, for test tubes used for the drawing, transport and/or analysis of blood. The safety closing device includes an undercap and a cap, both with central portions made of a perforable material. The central portion of the undercap is sealingly locked on the edge of the test tube and the central portion of the cap is sealingly locked on the side facing the undercap. A locking mechanism, that can only be intentionally disengaged, mechanically couples the cap to the undercap, and secures the cap/undercap assembly onto the prearranged open end of the test tube.

Abstract: In an apparatus for measuring the rate of erythrosedimentation of the blood a bell mouthed test tube is provided, having a cylindrical part in which a calibrated and graduated sealing tube, topped with an overflow sleeve for the excess blood, slides. This overflow sleeve allows an automatic filling with blood of the calibrated tube independently from the care taken in the filling of the tapered test tube.