Maraflex thread from Guterman, Col 111 has Micro core Technology.
Maraflex is the elastic sewing thread for household sewing machines. Maraflex is made with the unique Micro Core Technology® (MCT). It creates elastic seams using straight stitch easily – without an overlock or coverlock sewing machine.
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deal for sewing round necklines, tight seams, cuffs on legs and sleeves.  Sew closing and backstitch seams.
 
Use with straight stitch only, with a stitch length of 4 stitches per cm (approx 2.5mm stitch length).
Sew with thread in needle and bobbin. May need to loosen the tension, (fabric depending)
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Needle type - Jersey / Stretch or Super Stretch - size 70 - 80.
 Made from 100% Polybutylene Terephthalate for a high stretch..