Sewing Machine Bobbins: The Complete Guide
Every sewing machine takes a specific bobbin. The wrong one can jam the machine, throw off tension, or simply not fit — forcing an incompatible bobbin into a machine can damage it. This guide covers the bobbin classes Sewphee carries, how to tell which one your machine needs, and which product fits.
Why bobbin class matters
"Bobbin class" refers to the shape and size standard a bobbin is built to, not the brand printed on the box. A Class 15 bobbin fits a Class 15 machine regardless of who made it; a Class 66 bobbin does not fit a Class 15 machine no matter how similar it looks. Get the class right first — then choose plastic or metal, and the pack size you need.
The five bobbin classes Sewphee carries
| Class | Also fits | Dimensions | Sewphee product |
|---|---|---|---|
| Class 15 | Many Janome, Kenmore, Brother, Elna, Singer, and Baby Lock top-loading (drop-in) machines | 20.3mm outer diameter, 6.1mm inner diameter, 11.5mm height (7/16 in) | Class 15 Bobbins — plastic vs. metal guide |
| Class 66 | Older Singer front-loading machines and some drop-in machines. Not interchangeable with Class 15. | See product listing | Class 66 Bobbins — guide |
| SA156 | Many Brother sewing and embroidery machines. Similar size to Class 15 but Brother-spec — do not assume interchangeability. | See product listing | SA156 Bobbins — guide |
| 9033P (Pfaff) | Most Pfaff machines in the Creative, Expression, Tiptronic, and Hobby lines. Pfaff uses its own bobbin spec — do not substitute Class 15. | 21.6mm length, 8.8mm height | Pfaff 9033P Bobbins — guide |
| Husqvarna-specific | Many Husqvarna Viking machines — check your model's bobbin type before ordering, Husqvarna's range spans more than one bobbin system | See product listing | Husqvarna Bobbins — guide |
Find your bobbin by machine brand
Still not sure?
Check your machine's manual for the bobbin class or model number, or use the Compatibility Check on the Sewphee homepage. You can also send us your machine model and we'll help confirm the fit before you order.