есть готовый чёртёж короба на Phoenix Bass Machine 15

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?