Section 225.903 - Exempted supplies(b)(i) For an explanation of the term "supplies," see PGI 225.903(b)(i).(ii) The duty-free certificate shall be printed, stamped, or typed on the face of, or attached to, Customs Form 7501. A duly designated officer or civilian official of the appropriate department or agency shall execute the certificate in the format provided at PGI 225.903(b)(ii). 70 FR 73155 , Dec. 9, 2005