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.