The attachment is a zipper foot. The foot moves from side to side not the needle. I learned to sew at 10 on my Mothers treadle machine that my Father motorized. It only did straight stitching and I put many, many zippers in with that zipper foot. I also had the buttonhole attachment in that same pink box that I used on my 1960 Singer 401A. I had 3 little girls and made a lot of buttholes with that great attachment. I sold it for $5! Who knew!