Container preform with stepped interior finish

A finish portion of a preform for rotatably engaging with a closure to seal pressurized contents within an interior of a container formed from the preform, the finish portion comprising:

• a cylindrical body that begins at an opening to the interior and extends to and includes a tamper evidence ledge, the cylindrical body defining a stepped interior surface including
• a sealing surface adjacent to the opening for cooperating with a plug seal of the closure to seal the contents with the container;
• a first transition surface extending from the sealing surface to a handling surface positioned between the sealing surface and the tamper evidence ledge, the handling surface configured to receive equipment to form the preform into the container;
• and
• a second transition surface extending from the handling surface to an interior surface of the preform.

A finish portion of a preform for rotatably engaging with a closure to seal pressurized contents within an interior of a container formed from the preform, the finish portion comprising:

• a cylindrical body that begins at an opening to the interior and extends to and includes a tamper evidence ledge;
• a bevel disposed at the opening and configured to receive a plug seal of the closure;
• and
• a stepped interior comprising a graduated narrowing extending from the opening through the cylindrical body,
• wherein the stepped interior is configured to compressibly receive a plug seal comprising graduated seals configured to engage with the graduated narrowing,
• wherein the graduated seals include one or more diameters suitable for engaging with the graduated narrowing of the opening so as to seal pressurized contents within the container.