I purchased new bobbins for my favorite vintage featherweight because I use it so much. My machine wouldn't sew, just wadded up underneath. I thought it was my machine but, low and behold, it was only when I tried to use a new bobbin! I held them up next to my old ones which came with the machine and they were one metal thickness wider in width. Threw them in the garbage. I stick with the old ones now. My advice to people who are going to buy bobbins is to be sure to take their old one along and compare them before making the purchase.