N.Y. Comp. Codes R. & Regs. tit. 20, § 528.12
(1) For purposes of this section, the term flag means a light, flexible material, usually rectangular, and bearing one or more symbols or designs to indicate nationality or party. The term also includes related accessories to be used solely for the display of the flag, provided such accessories are sold with the flag for a single charge. For example, this includes a pole, rod, or staff; base or bracket; halyard; lanyard; or finial.
(ii) Kits composed of plastic parts which when assembled resemble a flag are not flags.
(2)
Tax Law, § 1115(a)(11)
(a) Exemption.
Sales of the flag of the United States of America and the flag of New York State are exempt from tax.
(b) Definitions.