Inphinity

I am starting to do some watch straps. There is a lot of information about finishing edges for sure, but a friend of mine bought a new watch strap and i am curious about the finishing method. Please see pictures. Apparently they made the edge by gluing the upper skin to the side of the strap. Instead of using dies/burnishers, they use the skin to finish the edge. The question is... How they do that? How they cut the upper skin to fit the edge? Sorry for my bad english.

Another pic...

I am starting to do some watch straps. There is a lot of information about finishing edges for sure, but a friend of mine bought a new watch strap and i am curious about the finishing method. Please see pictures. Apparently they made the edge by gluing the upper skin to the side of the strap. Istead of using dies/burnishers, they use the skin to finish the edge. The question is... How they do that? How they cut the upper skin to fit the edge? Sorry for my bad english.