We've got a sewing team at the church who works to make items for needy children and these Type A bobbins work great on our Singer sewing machines. They are well made, fully loaded with polyester thread, and save our team a lot of time. One note: this is fine thread and the strength is not great. Consider your job before buying. Recommended.
These bobbins are well wound and the stitch quality was great. Make sure you have the correct size bobbin. I thought they would fit both of my sewing machines but they only fit one. The bobbin was too large for the other. I don't know if you can see the stitch quality on the fabric but it is perfect. The white stitches are the ones from the bobbins. I'm happy with these bobbins and will save time not winding bobbins.
These bobbins appear to work in my Brother PE-770 embroidery machine. Unfortunately, I've been having a lot of problems with my machine, basically since I got it. The day I wanted to stitch something and used one of these bobbin, the design I was trying to stitch was just not coming out right. I, of course, slightly suspected this bobbin since it was a pretty big unknown in a machine that's been notoriously finicky. However, after I switched to one that came with the machine, it didn't change the results one bit and I ended up giving up on that design. But, I wouldn't hesitate to use these bobbins again when I get around to trying to use my embroidery machine again. Update: I used the purple bobbin from the box of colorful bobbins and it worked great. I think maybe the design I was stitching earlier might have been a problem, but this time I just stitched out a new quilt label and didn't have any problems. It's nice to have a prewound bobbin that so closely matched the top thread that I used for my latest quilt label.