SL3314 is a 3, 4 thread overlocking with differential feed overlocker and features:

  -  Adjust the ratio, by turning the dial.
  -  The adjustable differential feed helps produce quality seams,
      gathers and frills.
  -  Bite width ensure correct width of the stitching to suit the fabric
      type.
  -  Built in stitch length adjuster allows wide variation of stitch
      length.

Please use a Roll hem Needle plate B & a B-foot for roll hem.