The FFD4x4x4 tool works on the free form. The use of these tools is to stretch the free model.
Sep1: Create a box and click modify tab then select FFD4x4x4 tool.
Fig.30
Step2: Click on the flip arrow of the FFD 4x4x4 tool. Then select control point option.
Fig.31
Step3: Select scale tool and select some control point.
Fig.32
Step4: After that click on X-axis and drag up or down side.
Fig.33