A hemostasis valve body provides strong sealing around a medical device during insertion of the medical device into a blood vessel, low forces for tearing, and stability during insertion of the medical devices as well as during peel away. The valve body comprises a first surface, a second surface opposite the first surface, an edge, helical slits, and a pair of longitudinal cuts. The helical slits are positioned at a center of the valve body and traverse the first surface to the second surface. The helical slits provide a seal around the medical device. Each respective longitudinal cut extends from the first surface partially through the valve body to a depth short of the second surface for at least part of a length of the respective longitudinal cut. The longitudinal cuts facilitate a separation of the valve body into two parts during a peel away action.
