Singer 15-91 direct drive (no belt) is electric and the 15-88, 15-89, 15-90 have belts and are threadles or can be threadled. Some might have a potted motor. Most are not anything you would take along to sew at class with the exception of the Feather weight and Singer 301. Both of those only do straight stitch. the 401 has build in stitches and cams, little palsitc dishes that enable you to do more decorative stitches.
Singer 15-91
[ATTACH=CONFIG]246440[/ATTACH]
Singer 201
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Singer 401
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Singer Red Eye threadle
[ATTACH=CONFIG]246443[/ATTACH]
Singer Feather Weight portable
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Singer 301 in cabinet but is also lighter and portable
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