The color brown is said to represent ruggedness when used in advertising .  Pullman Brown  is the color of the United Parcel Service (UPS) delivery company with their trademark brown trucks and uniforms; it was earlier the color of Pullman rail cars of the Pullman Company , and was adopted by UPS both because brown is easy to keep clean, and due to favorable associations of luxury that Pullman brown evoked. UPS has filed two trademarks on the color brown to prevent other shipping companies (and possibly other companies in general) from using the color if it creates "market confusion". In its advertising, UPS refers to itself as "Brown" ("What can Brown do for you?").