Once I got one shipped to be which wasn't broken (thanks Amazon), I discovered that the picture I have, which has a double mat, can't be made to fit-- it's too thick and the slot it goes into too thin for the frame to work. Similarly a single-mat item wouldn't work; while it would fit into the slot there's not enough space for the frame's backing to go back on in order to have something to hang the whole business by. So unless you're framing just a single sheet (photo or etc), don't bother.