Single 15-inch Rectangular Vented In-Vehicle Subwoofer Box - 65 L / 33 Hz - 633 × 430 × 387 mm

Can you explain the height, width, and length of the port?

Can you please explain the height, width, and length of the port? I have changed the height of the port to different numbers but the 3d rendering does not show any changes. I don't understand. When I go to view the parts, none of the dimension change. What part of the port does height and width signify?