limit is met the continued vertical movement is translated to the button 42 causing the button 42 to move upward button retention bead 18 overcomes the resistance implied to restrict vertical travel by upper container bead 31 a and the button 42 insert 40 and closure 10 can be removed from the container further the contents of the dosing chamber 12 are emptied into the container prior to removal of the closure from container the combined multi piece closure 10 of the present invention may be utilized with pressurized container contents such as carbonated beverages in use with pressurized contents seal 16 may be biased upwardly as is shown in order to allow internal container pressure to more readily infiltrate dosing chamber 12 after the container is filled and capped pressure within the container caused by the carbonation increases and can infiltrate the dosing chamber 12 thus the chamber 12 becomes pressurized with the additive contents the multipiece closure 10 is designed to allow release of the internal container pressure first followed by opening of the dosing chamber 12 causing spraying of the additive through the flow path 53 due to pressurization of the dosing chamber in fig4 initial release of the pressure within the container through pressure flow path 52 is depicted unthreading of the closure 10 from the container neck 30 separates the lower surface of the insert top wall 21 from the container rim the button retention bead 18 may be notched as depicted in the embodiment of fig4 such that notch 15 provides a flow path to release the pressure within the container multiple notches or gaps 15 may be provided to provide adequate pressure release flow paths this may work in combination with the pressure flow paths 55 formed in.