Abstract: A one-piece hemostasis valve located within a longitudinally extended housing, with the valve comprising an extended sealing neck having a passageway therethrough, communicating with a sealing chamber having opposing sealing exit lips and preferably support shoulders on the outside of the valve adjacent to the sealing neck to provide support for the valve. The passageway of the extended sealing neck contains narrowed and broadened portions to prevent blood loss when receiving a guidewire and catheter inserted through the passageway of the sealing neck.

Abstract: Disclosed herein is a hemostasis valve which is formed of a longitudinally extended valve housing having a first opening and a central longitudinal passage communicating with an opposite second opening. A cap means is providied for enclosing the first opening of the housing, said cap means having a hole to permit insertion of a catheter. Also provided is a one-piece seal means located within the longitudinally extended housing, said seal means comprising a sealing neck having a relatively small opening therein and communicating with a sealing chamber having opposing sealing exit lips which are both readily expandable to a diameter less than that of the valve housing upon insertion of a catheter.