Lapierre Little Magic Bobbin Washers ~ Little Magic Bobbin Genies ~Size L Bobbin Cases ~ 12ct Special size for home sewing machines with top drop-in bobbin size "L" bobbin cases. Eliminates backlash & bird's nests on the underside of your quilt! Easy to use! Just drop Bobbin Genie into the bobbin case. Replace bobbin and insert into the machine. You're ready to sew! Long lasting! Super slippery, touch and durable! Designed by: Sharon Schamber Use during free-motion quilting, thread painting or embroidery when changing directions at high speed.