When securing an intermodal container on a chassis, what is the maximum allowable vertical travel when secured?

A 1 inch

explanation

Securing devices must restrain the container from moving more than:
1.27 cm (1/2 in) forward.
1.27 cm (1/2 in) rearward.
1.27 cm (1/2 in) to the right.
1.27 cm (1/2 in) to the left.
2.54 cm (1 in) vertically.