(EN) A plastic aerosol container assembly (10) includes a plastic container that has a main body portion (12) defining an interior space and a finish portion (14) that defines an opening. A pressurized aerosol mixture is maintained within the interior space. The finish portion has an inner surface (20) that has an undercut (22) defined therein. An aerosol valve assembly (24) is mounted to the plastic container so that a portion thereof engages the inner surface (20) of the finish portion (14) so as to be retained by the undercut (22). The plastic container is preferably fabricated from material including polyethylene terephthalate (PET). At least one location in the finish portion may be crystallized in order to provide enhanced resistance to stress cracking.