A flow control device (40) for controlling the flow of a pressurized fluent substance is disclosed. The device (40) includes a housing (44, 48, 52) having an inlet portion (44) for receiving the fluent substance, an outlet portion (48) for discharging the fluent substance, and a platform (52). The device (40) further has a valve (56) located within the housing (44, 48, 52). The valve (56) is located between the platform (52) and the outlet portion (48). The valve (56) has a flexible, resilient valve head portion (160) that has confronting, openable portions (212, 216) movable from a closed configuration to an open configuration when the valve head portion (160) is subjected to a pressure differential acting across the valve head portion (160).
