A material supply assembly comprising: a valve assembly including: an outer valve member and an inner valve member, the outer valve member including an annular outer body section and an outer discharge section, the outer discharge section including a plurality of first openings therein, the inner valve member including an annular inner body section and an inner discharge section, the inner discharge section including a plurality of second openings therein, the inner valve member being rotatably disposed on the outer valve member and rotatable relative to the outer valve member between a closed position at which the valve assembly is closed and an open position at which the valve assembly is open, the plurality of first openings being aligned with the plurality of second openings at the open position, a first circumferential seal between the outer and inner valve members, the first circumferential seal providing a seal between the outer valve member and the inner valve member; and a base having a receptacle with an inlet and an outlet, the inlet being configured to receive at least a portion of the valve assembly therein and the outlet being configured to pass material therethrough, the material supply assembly being characterized by a plurality of discharge seals between the outer valve member and the inner valve member, one of the discharge seals extending around each of the first openings of the outer valve member or each of the second openings of the inner valve member to provide a seal between the outer valve member and the inner valve member. an outer valve member and an inner valve member, the outer valve member including an annular outer body section and an outer discharge section, the outer discharge section including a plurality of first openings therein, the inner valve member including an annular inner body section and an inner discharge section, the inner discharge section including a plurality of second openings therein, the inner valve member being rotatably disposed on the outer valve member and rotatable relative to the outer valve member between a closed position at which the valve assembly is closed and an open position at which the valve assembly is open, the plurality of first openings being aligned with the plurality of second openings at the open position, a first circumferential seal between the outer and inner valve members, the first circumferential seal providing a seal between the outer valve member and the inner valve member; and the inner valve member including an annular inner body section and an inner discharge section, the inner discharge section including a plurality of second openings therein, the inner valve member being rotatably disposed on the outer valve member and rotatable relative to the outer valve member between a closed position at which the valve assembly is closed and an open position at which the valve assembly is open, the plurality of first openings being aligned with the plurality of second openings at the open position, a first circumferential seal between the outer and inner valve members, the first circumferential seal providing a seal between the outer valve member and the inner valve member; and a base having a receptacle with an inlet and an outlet, the inlet being configured to receive at least a portion of the valve assembly therein and the outlet being configured to pass material therethrough, the material supply assembly being characterized by a plurality of discharge seals between the outer valve member and the inner valve member, one of the discharge seals extending around each of the first openings of the outer valve member or each of the second openings of the inner valve member to provide a seal between the outer valve member and the inner valve member.