In boxes or crates, having a density of 8 pounds or greater per cubic foot, Density must be shown by shipper on shipping orders and bills of lading at time of shipment. If density is not shown and shipment is inadvertently accepted, class will initially be assessed under the provisions of item 158880, naming 'Toilet Bowls, NOI, or Toilet Tanks, NOI.' Upon satisfactory proof of actual density, class will be adjusted accordingly.