The documentation of the GK coverstitch series is lacking information.
The handbook of a similar Singer product showing the different stitches
and the thread tension may be of help. Click on the link to download
this Singer handbook. HERE
Elna handbook. HERE
Different stitches of an Elna coverstitch sewing machine HERE
The letter "B" on the model's name stands for incorporated light.
Other manuals:
Manual Collareta GK257B/357B en Español
Manual FN2 Overlock series - English
Manual Overlock series FN2 en Español
Manual Overloque série FN2 em Português
Manual Overloque GN1 em Português
Manual Galoneira GK257 GK357 em Português
