A real-world example of how the mark is actually used on goods or in the offer of services.
Labels, tags, or containers for goods are considered to be acceptable specimens of use for a trademark. For a service mark, specimens may be advertising such as magazine advertisements or brochures. Actual specimens, rather than facsimiles, are preferred. However, if the actual specimens are bulky, or larger than 8 " x 11", then the applicant must submit facsimiles, (e.g., photographs or good photocopies) of the specimens. Facsimiles may not exceed 8 " x 11". One specimen is required for each class of goods or services specified in the trademark application.
Specimens are required in applications based on actual use in commerce, Section 1(a), 15 U.S.C. S1051(a), and must be filed with the Amendment to Allege Use, 15 U.S.C. S1051(c) , or the Statement of Use, 15 U.S.C. S1051(d), in applications based on a bona fide intention to use the mark in commerce, Section 1(b), 15 U.S.C. S1051(b). Specimens are not required for applications based on a foreign application or registration under Section 44 of the Trademark Act, 15 U.S.C. S1126, or for applications based on an extension of protection of an international registration to the United States under Section 66(a) of the Trademark Act, 15 U.S.C. S1141f.
Source: U.S. Patent and Trademark Office.