Presser

n.
  1. One who, or that which, presses.
    2. Presser bar, or Presser wheel (Knitting machine),
    a bar or wheel which closes the barbs of the needles to enable the loops of the yarn to pass over them.
    Presser foot ,
    the part of a sewing machine which rests on the cloth and presses it down upon the table of the machine.