Abstract: The invention relates to a volatile composition dispenser. The volatile composition dispenser comprises a sealed reservoir containing a volatile composition, a membrane surrounding at least part of the sealed reservoir, and a rupture mechanism formed of a single piece of plastic located between the membrane and the sealed reservoir. The rupture mechanism comprises a support, and a movable portion attached to the support at a proximal end of the movable portion by at least one connection member. The connection member has a depth less than the depth of the movable portion and/or a width less than the width of the movable portion. One or more rupture elements are located at a distal end of the movable portion, wherein the distal end of the movable portion is movable relative to the support upon activation. Upon activation of the rupture mechanism, the one or more rupture elements are moved into contact with the reservoir such that they puncture the reservoir to release the volatile composition.