A crown assembly includes a crown cap and a crown stem. The crown cap includes a first top plate and a first side plate that together form a crown cap groove. The crown stem includes a stem body and a stem connection portion including a second top plate and a second side plate that together form a crown stem groove. A plastic connector is disposed between the crown cap and the crown stem and includes a third top plate and third side plate that together form a connector groove. A portion of the crown stem is inside the crown cap groove. The connector groove is in the crown cap groove and the crown stem groove is in the connector groove. The crown cap groove, the connector groove, and the crown stem groove each open in an axial direction substantially perpendicular to an outer surface of the first top plate.