Brother Free Arm LX-3125 repair/ replacement parts. Bobbin case, class 15 universal #JO-1313Z, with class 15 bobbin and shuttle hook, class 15, universal #2515Z and shuttle race cover. Pin at bottom and side indents for latches to hold in place.  Guaranteed to fit Brother LX-3125 and may work on other class 15 front loading machines. Race cap spring may be only difference to other models.  Price includes shipping to lower 48.