Except it seemingly can't actually be used.
The thing is, it's the size of a MicroSD card:

If I attach the eMMC module so that it overlaps the board, it triples the thickness and the adapter board can't be inserted in a microSD slot. If I attach it so that it extends out past the adapter:
a)It's wobbly and unstable, and
b)I get an error when inserting the clumsy stack, on two different PCs running different operating systems.
So ...not useful.
I even tried another eMMC module. No dice.
So, experts, please weigh in: is my adapter defective? Is it just a bad design?
Thanks.