A splittable sheath includes a splittable sheath body, a splittable sheath hub, and a valve element. The sheath body comprises a generally flexible tubular structure, a proximal end, and a distal end. The sheath body defines a longitudinal axis and is splittable into two halves along a pre-determined line generally parallel to the longitudinal axis. The sheath hub extends from the proximal end of the sheath body and defines a longitudinal axis generally aligned with the longitudinal axis of the sheath body. The sheath body and sheath hub form an inner cavity along their respective longitudinal axes. The valve element includes a resilient plate and a sealing element. The resilient plate includes a distal portion extending radially inwardly from a side of the inner cavity. The sealing element includes a sealing surface and is supported by the resilient plate such that the sealing element is biased toward a position against a second sealing surface on at least one of the splittable sheath body and hub to substantially seal the inner cavity.
