A closure assembly for a container including an internally-threaded annular flange, an externally-threaded closure plug that is received by the annular flange, and an annular gasket positioned between the annular flange and the closure plug for establishing a sealed interface. The container includes a container end panel that is formed over and around a portion of the annular flange and provides an inner axial wall that is positioned between the annular flange and the annular gasket. The clearance between the closing plug and the inner axial wall relative to the size of the annular gasket determines the degree of radial compression of the annular gasket as the plug is threaded into the flange. A radial lip of the plug is designed to contact an upper surface of the container end panel that is formed over the flange as a visual indication when the required tightening torque of the plug within the flange has been reached.