Abstract: A hemostasis valve gasket for use in an introducer which is integrally formed from an elastomeric material so as to exhibit resiliency and which is designed to close about small diameter objects, such as a guide wire and about larger diameter objects such as a working catheter or guide catheter to prevent air or blood leakage. The gasket includes a proximal cylindrical member, a distal cylindrical member and a central member which is spaced in its center portion from the proximal and distal members by chambers or cavities. One of the proximal or distal cylindrical members has a bore of a relatively small diameter compared to that formed through the other and an angled slit is formed through the central member in general alignment with the bores formed through the outer proximal and distal cylindrical members.