Vintage Neatspan Expanding Curtain Rod Tin

Interesting old item which is generally in good condition. It does however have a dent which should be easy to remove by taking the lid off and pushing it out . I have been reluctant to do this purely because I should imagine the contents are a bit springy and maybe a problem getting it back in .
The tin measures approximately
9.5 cms high
15.5 cms diameter
Please study the photos for a better description