These large M-Class bobbins are designed to hold more thread than a regular bobbin, letting you quilt longer without needing to change it. They come in a pack of 10 bobbins and are made of a high quality aluminum. These will work with the Q'nique 14+ and Q'nique 15R, Q'nique 15M and the Q'nique 21, as well as most other longarm quilting machines.