ok, first of all, you need to find your model number of your singer sewing machine---you really cannot buy bobbins for Singer machines without this---there are so many different kinds and the ones at JoAnns are generic
Now you can google: singer sewing machine #____ bobbins and companies that carry them will come up or you can try www.sewingmachinesplus.com/singerbobbins and find your model number and click on it---if you cannot find it on the list, then contact them via email---they are very nice people