DISCONTINUED: Bilt Well Casement Operator, Large 7/8 inch Nylon Button, 14-1/2 Straight Arm measured from the center of the operator to the center of the button. DISCONTINUED ITEM - The replacement has a smaller nylon button and requires changing the operator and metal track on window sash. Replace with # 55037 operator with 13-1/2 inch arm and 4 screw hole, 11-3/8 track # 55160. Handle, if need part # 55311