I can't see it being for crunches, are you sure? Look at any other ab-type platform. They are wider and longer. If your legs went over the hump, your shoulders would be off the other end. And it's too narrow to keep your legs together on the hump, at least for anyone with decent sized thighs.
We can imagine all kinds of things one could do on this here bench... but what's it called, and what is it really for? If it IS for crunches, does it have a name or can you find other examples of one?
Thanks for any and all help.