Mail Sorting Unit 24D-2, used by USPS employee, Emma Thornton, from the Church Street Post Office Station, New York, NY. It was last used on September 11, 2001, the day of the attack on the World Trade Center. The mail sorting unit is a table with a sorting case attached to the back of the table top. Six cardboard shelves have been added to provide additional sorting units. This sorting unit was used to sort mail for various routes inside the World Trade Center. Some of its stops included Cantor Fitzgerald, Fred Alger and Met Life.