These plastic bobbins are used on most new Singer sewing machines. They are 15k class and suitable for front loading or top loading sewing machines.
LORJE Sewing Machine Class 15 Metal Bobbins(10pc)
Metal Bobbins - Australia
Plastic sewing machine bobbins - Bernette
Haberdashery Archives — Page 14 of 43 — S E Simons
Crafts, Sewing, Sewing Machine Parts & Accs | !
Singer Heavy Duty 4411, 4423, 4432, 5523 Genuine Singer Accessories
Milward Universal Class 15k Plastic Bobbins 3 Pack
Metal Bobbins - Suits - Singer – The Eternal Maker
Singer Fashion Mate 3333, 3337, 3342 Genuine Singer Accessories
Singer Inspiration 4200 Series Surefit Bobbin Pack Of 3 (359838900
SINGER HEAVY DUTY 4411, 4423, 4432, 5523 Genuine Singer Accessories £1.50 - PicClick UK