A valve device (100, 500) comprising: a valve mechanism comprising a conduit separated into a first section and a second section by a pocket having a sprung gate (128, 228, 228', 228") seated therein, wherein inner dimensions of both of the first section and the second section gradually narrow toward the pocket; an actuator connected to the sprung gate; wherein the actuator moves the sprung gate linearly within the pocket between an open position and a closed position relative to the conduit; characterized in that the sprung gate comprises: a first gate member (130, 230, 230', 430) and a second gate member (132, 232, 232', 432), each defining an opening (233, 233', 433) therethrough in an open position portion (240, 240') thereof; an endless elastic band (134, 234, 235, 346, 348, 434) having an inner perimeter (282, 272, 273, 476) defining at least a first open space sandwiched in compression between the first and second gate members with the open space thereof oriented for alignment with the opening in both of the first and second gate members, which are aligned to form a passage (229, 229', 429) through the sprung gate; and wherein the endless elastic band (134, 234, 235, 346, 348, 434) applies a bias force to the first and second gate members biasing them away from one another toward opposing walls of the pocket and wherein the first gate member (130, 230, 230', 430) includes a fastener (281, 481) connected to a fastener receiving member (283, 483) of the second gate member (132, 232, 232', 432) thereby securing the first and second gate members together. a valve mechanism comprising a conduit separated into a first section and a second section by a pocket having a sprung gate (128, 228, 228', 228") seated therein, wherein inner dimensions of both of the first section and the second section gradually narrow toward the pocket; an actuator connected to the sprung gate; wherein the actuator moves the sprung gate linearly within the pocket between an open position and a closed position relative to the conduit; characterized in that the sprung gate comprises: a first gate member (130, 230, 230', 430) and a second gate member (132, 232, 232', 432), each defining an opening (233, 233', 433) therethrough in an open position portion (240, 240') thereof; an endless elastic band (134, 234, 235, 346, 348, 434) having an inner perimeter (282, 272, 273, 476) defining at least a first open space sandwiched in compression between the first and second gate members with the open space thereof oriented for alignment with the opening in both of the first and second gate members, which are aligned to form a passage (229, 229', 429) through the sprung gate; and wherein the endless elastic band (134, 234, 235, 346, 348, 434) applies a bias force to the first and second gate members biasing them away from one another toward opposing walls of the pocket and wherein the first gate member (130, 230, 230', 430) includes a fastener (281, 481) connected to a fastener receiving member (283, 483) of the second gate member (132, 232, 232', 432) thereby securing the first and second gate members together. a first gate member (130, 230, 230', 430) and a second gate member (132, 232, 232', 432), each defining an opening (233, 233', 433) therethrough in an open position portion (240, 240') thereof; an endless elastic band (134, 234, 235, 346, 348, 434) having an inner perimeter (282, 272, 273, 476) defining at least a first open space sandwiched in compression between the first and second gate members with the open space thereof oriented for alignment with the opening in both of the first and second gate members, which are aligned to form a passage (229, 229', 429) through the sprung gate; and wherein the endless elastic band (134, 234, 235, 346, 348, 434) applies a bias force to the first and second gate members biasing them away from one another toward opposing walls of the pocket and wherein the first gate member (130, 230, 230', 430) includes a fastener (281, 481) connected to a fastener receiving member (283, 483) of the second gate member (132, 232, 232', 432) thereby securing the first and second gate members together.