The letters of the shipping name on a portable container with a capacity of less than 1,000 gallons must be _________.

Portable tanks also must show the lessee or owner's name and display the shipping name of the contents on two opposing sides. The letters of the shipping name must be at least 2-inches tall on portable tanks with capacities of more than 1,000 gallons and 1-inch tall on portable tanks with capacities of less than 1,000 gallons.
The ID number must appear on each side and each end of a portable tank or other bulk packaging that holds 1,000 gallons or more and on two opposing sides, if the portable tank holds less than 1,000 gallons. The ID numbers must still be visible when the portable tank is on the motor vehicle. If they are not visible, you must display the ID number on both sides and ends of the motor vehicle.