Fitment for a container neck

1. A closure for a container neck,

the closure comprising a shell and a fitment releasably retained within the shell,

the fitment configured to be inserted into an operative position within a container neck having a bore diameter D when the closure is applied to the container neck;

the fitment comprising a body and engagement means extending radially outwardly from the body;

the engagement means in an extended condition relative to the body and releasably engaged with the shell, to releasably retain the fitment within the shell prior to application of the closure to the container neck, the engagement means defining a first span S 1 that is greater than the bore diameter D when in said extended condition, and

the engagement means configured to be forced into a retracted condition relative to the body during insertion of the fitment into the container neck, to release the fitment from the shell, the engagement means defining a second span S 2 that is less than the bore diameter D when in said retracted condition;

the engagement means enclosed within the container neck when the fitment is in the operative position.

2. A closure as claimed in claim 1 , wherein the engagement means resiliently engages the shell when in the extended condition.

3. A closure as claimed in claim 1 , wherein the engagement means is configured to engage the container neck when in the retracted condition.

4. A closure as claimed in claim 3 , wherein the engagement means is configured to resiliently engage the container neck when in the retracted condition.

5. A closure as claimed in claim 1 , wherein the engagement means comprises a plurality of engagement members.

6. A closure as claimed in claim 5 , wherein the shell comprises an annular bead, and each engagement member comprises a lug co-operable with the annular bead.

7. A closure as claimed in claim 5 , wherein the body is tubular, and the engagement members of the plurality of engagement members are equidistantly spaced around a circumference defined by the body.

8. A closure as claimed in claim 1 , wherein a transition of the engagement means from the extended condition to the retracted condition comprises one of: a smooth transition phase, a snap transition phase.

9. A closure as claimed in claim 1 , wherein the fitment comprises at least one annular fin for engaging the container neck when the fitment is in the operative position.

10. A closure as claimed in claim 1 , wherein the fitment is a pourer fitment.

11. A closure as claimed in claim 10 , wherein the fitment is a non-refillable pourer fitment.

12. A closure as claimed in claim 1 , wherein the fitment is an aerator fitment.

13. A closure as claimed in claim 1 , wherein the shell comprises a liner for sealing against a container neck rim.

14. A closure as claimed in claim 1 , wherein the shell is a metal shell.

15. A closure as claimed in claim 14 , wherein the shell is an aluminium shell.

16. A method of providing a container neck with a fitment, the method comprising the steps of:

receiving a closure as claimed in claim 1 ,

receiving a container comprising a container neck having a bore diameter D, and

applying the received closure to the received container to insert the fitment into the container neck into the operative position.

17. A method as claimed in claim 16 , wherein the container neck is a container neck of a glass bottle.

18. A container comprising a container neck having a bore diameter D, the container neck provided with the closure of claim 1 .

19. A container as claimed in claim 18 , wherein the container is a glass bottle.