Singer S900 Manuel D'instruction page 60

Ric-rac is primarily used for a decorative top-stitch. It is ideal
for edging neck-bands, armholes, sleeves and hems. When
manually adjusted to a very narrow width, it also can be used
for sewing high stress seams.
overcasting in one operation. It is primarily used on slightly
stretch fabrics and non-stretch fabrics such as linen, tweed,
and medium to heavy-weight cotton.
Used primarily for decorative machine stitching.
Useful for decorative stitching on borders and for use in
heirloom sewing. The Entredeux stitch is most often sewn with
stitch pattern.
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