I have two brothers too. The difference in the bobbins is the height of the bobbin. I have a front loader and I can use any bobbin height bobbin in it. DH got me a computerized one for my birthday and first page in the manual has a huge warning about the bobbin it has to be to taller one for that machine. Hope that helps!! Ps I use the metal singers bobbins(thats what I can get here) for the computerized and they do fit in the regular brother as well.