I am just a hobbyist and found a 10 pack of extra bobbins was nice to have . I keep 2 each of my popular colors or thread size available , so if you run out or coming close you don't have to stop and go through the winding process. You will need to do some searching to find a reasonable price but I found it was worth a extra dollars. I always have a few if not more empty and ready to go , so I can do a one off without wasting thread.