| 摘要 |
A cap for a blood-sampling tube has a collar adapted to fit on the tube and a tubular extension extending from the cap, defining an axis and having an outer end remote from the cap. An annular wall is formed inside the cap spaced from the outer end and an annular lip projects axially backward from the outer end and has an outer surface spaced radially inward of an inner surface of the extension and an axially directed inner end. A pierceable flat membrane in the extension on the annular wall snugly engages the inner surface of the extension and has an outer face spaced axially from the inner end of the lip. The lip has an inner surface defining a cylindrical passage of a predetermined diameter and the wall has an inner edge defining a similarly dimensioned coaxial annular passage. |
