Abstract: An automotive seat back (34) which comprises a pair of spaced upright members (40) each having lower ends rotatably supported on pivot pins (38) and interconnected by a cross member (42) extending between the upper ends. A shoulder belt housing (44) extends upwardly between the upright members (40) from below the cross member (42) to a distal end (46) disposed above and outside the cross member (42). Crisscrossing truss elements (52) interconnect the upright members (40) and the housing (44) to suspend the housing (44) within the periphery of the seat back as defined by the upright members (40) and the cross member (42). The upright members (40) and the cross member (42) and the truss elements (52) and the housing (44) are all integrally die cast of magnesium. The housing (44) includes a coffin portion, defined by side walls (54) and a bottom (56), and a cover (58) disposed over and in sealing engagement with the side walls (54).