Roll-top plastic security carts have fixed-height shelves and a long door that rolls up to allow full access to the carts' shelves and rolls down to conceal the carts' contents. They are also called tambour trucks. The carts' door can be locked to prevent unauthorized access. The carts have a tapered floor with large drain openings that prevent liquids from collecting in the carts. They are made from plastic, which is lighter than metal and will not rust or dent. These carts can hold large volumes of bulk materials such as linens, towels, or trash and are often used in hospitality and catering operations. They can also be used for transporting food, beverages, sporting equipment, tools, and other items.