Tapped holes in Edwards folder tooling

[bricol]

What are they for -

http://www.ebay.co.uk/itm/Edwards-s...331250?hash=item2820f09bb2:g:qFAAAOSw9IpXwvxi

The holes towards the tips of the segments. Mine, which is not the one in the ad, has them too, with brass scews in. I've no idea what they are for.

Any ideas?