Dina, I have the quarter inch foot with the black piece of metal hanging down. I found that it was wobbly and the quarter inch seams weren't accurate, so I put a teeny piece of fabric between the rod across the foot and the clamp that snaps onto it. That did the trick. The foot was tight as a drum and didn't wobble anymore. I've never seen any other quarter inch foot. I'll have to check it out, thanks.