a device for collecting a blood sample from a plastic segment tube into a receptacle uses a cylindrical housing containing a hollow needle to puncture the segment tube as it is inserted into the upper port of the device . a series of ribs with medial edges are arranged in a radial pattern around the needle within the upper port to guide and support the segment tube as it is inserted . the ribs are separated by slots that also guide the sealed end of the segment tube . an annular recess around the lower port of the device holds the rim of the receptacle and allows blood released by the punctured segment tube to drain into the receptacle . the annular recess accommodates a wide range of test tube diameters , and exerts only a downward force on the rim of the receptacle when a segment tube is inserted into the upper port of the device .