2010-11. Adjust knob. black. Left.SEAT BACK COMPONENTS. Left.WAGON. Right.SEAT BACK COMPONENTS. Right.WAGON. A Knob on the side of the seat that is used to manually adjust the seat lumbar position. Handle used to adjust the recline angle of the seat back. Seat Adjustment Knob. Lumbar adjuster. Release lever. Seat Back Recliner Adjustment.