A TPE valve (20, 20A) includes a head (125, 125A) with a central axis (43) and has an interior surface (130, 130A, 132, 132A, 133, 133A), an exterior surface (134, 134A), and at least one self-sealing slit (140, 140A). The valve (20, 20A) includes a
peripheral attachment portion (120, 120A) spaced laterally from the head (125, 125A) and an intermediate portion (124, 124A) extending laterally from the head (125, 125A) to the
peripheral attachment portion (120, 120A). The intermediate portion (124, 124A) has an interior surface (126, 126A) and an exterior surface (127, 127A). The interior surface (130, 130A, 132, 132A, 133, 133A) of the head (125, 125A) and the interior surface (126,126A) of the intermediate portion (124, 124A) intersect at a first circular line of intersection (150, 150A). The exterior surface (134, 134A) of the head (125, 125A) and the exterior surface (127, 127A) of the intermediate portion (124, 124A) intersect at a second circular line of intersection (154, 154A). The first circular line of intersection (150, 150A) and the second circular line of intersection (150, 150A) are spaced an
axial distance no greater than about 0.30
millimeter.