Sewing on piping with a regular zipper foot can be difficult because it is hard to see where the seam allowance is. It can also be difficult to know how close to get to the piping. I used the invisible presser foot #35 to sew in fine piping onto the collar of an infant dress. The needle stays in the middle of the foot, so it is easy to stay on the 5/8″ line. The piping is fed in the left opening on the foot, so it actually aligns itself as you sew. There is no need to pin the piping ahead of time. The stitch line is exactly the same distance away from the piping throughout the sewing process. This process gives an even piping edge on the project.