N.C. Gen. Stat. § 8-42
When any person shall bring an action upon a contract, or shall plead, or give notice of, a setoff or counterclaim for goods, wares and merchandise by him sold and delivered, or for work done and performed, he shall file his account with his complaint, or with his plea or notice of setoff or counterclaim, and if upon the trial of the issue, or executing a writ of inquiry of damages in such action, he shall declare upon his oath that the matter in dispute is a book account, and that he hath no means to prove the delivery of any of the articles which he then shall propose to prove by himself but by this book, in that case such book may be given in evidence, if he shall make out by his own oath that it doth contain a true account of all the dealings, or the last settlement of accounts between himself and the opposing party, and that all the articles therein contained, and by him so proved, were bona fide delivered, and that he hath given the opposing party all just credits; and such book and oath shall be received as evidence for the several articles so proved to be delivered within two years next before the commencement of the action, but not for any article of a longer standing, nor for any greater amount than sixty dollars ($60.00).
N.C. Gen. Stat. § 8-42