Not required., 138 500 725 - 3 m Knocking Bar., 138 500 730 - 4 m Knocking Bar., 138 500 735 - 5 m Knocking Bar., 138 500 740 - 6 m Knocking Bar., 138 106 287 - Maximum Height Warning Sign., 138 100 991 - M16 Expanding Bolt (8 required per Height Restrictor)., 138 106 558 - Height Restrictor Catch Post., 138 100 906 - 40 mm Brass Padlock with 2 Keys.