Abstract: A restraint seat back recliner construction with a high strength double-wall recliner body that packages a lead screw mechanism inside the body to create a shoulder belt load carrying, single-sided, recliner system. A unique slot in the lower body is employed that guides the movement of a traveling nut pinion at the end of a lead screw and connects the upper and lower body, thereby providing reclining action and acting as a secondary safety stop mechanism. A unique end detail of a guide slot and a lead screw end pinion design permits controlled occupant deceleration during a frontal vehicle crash. Application of two-door, four-door, power, manual, single and double sided recliners are shown.