It is a zigzag foot....not a pleater or ruffler. I have both feet and this one lacks a lot of the goodies that the pleater/ruffler has. Its just to make it possible to zigzag or satin stitch with a straight stitch machine. I don't think it needs a wide hole in the plate below it because the fabric moves back and forth, not the needle. If you have a wide hole under it, using the solid plate with a hole like the one designed for the buttonhole attachment would help keep it from tangling in the feeddogs. Have fun playing with it, it takes a bit of getting used to.