La Pierre Studio (for longarm machines) Mega Genie Magic Bobbin Washers MG12
Special size for LONG-ARM MACHINES— M BOBBIN CASES! Just slip our easy-to-use Mega Genie Magic Bobbin Washers into your M bobbin case, and you're ready to go! Eliminates the backlash and bird's nests on the underside of free-motion quilting when changing directions at high speed. Tough and long-lasting.