why wont mouse over image work on my listings?

[dominator.029]

I have noticed that my listings do not have the feature that most other listings have in that the enlargement frature of mouse over picture

is not available..

How is this feature set to operate ??

Thanks  Ian 

[gem*addiction · Accepted solution]

All of your listings have it, it just doesnt show up on your own selling page as there is no need for it there.