The Bobbin Case is used as a replacement part for sewing machine with front-loading bobbin systems. It may also be used as a spare bobbin case in specialty sewing. Use only SINGER Class 15 Bobbins in Front-Loading Bobbin Systems.Genuine SINGER Accessory in carded blister pack. For use with sewing machine with class 15 front-loading bobbin systems, including brands Baby lock, Bernina, Brother, Elna, Euro-Pro, Husqvarna Viking, Janome, Juki, Kenmore, Necchi, New Home, Pfaff, Simplicity, White. Watch the video tutorial to learn how to correctly thread your front-loading bobbin system sewing machine.