These needles are designed and recommended for use with Elna's 704 DEX Overlocker, Janome's CoverPro Series Cover Stitch and 1200d Overlock/Coverhem Machines.
The adjustable seam guide is used to give consistent spacing between rows of decorative stitching and can also be used to guide the edge of your seam allowance.
A perfect addition to the CoverPro the hemming guide folds over a consistent width of fabric, making it easy to form hems, cuffs and other finished edges.