N.Y. Gen. Bus. Law § 599-a

§ 599-a. Prohibition on sale. It shall be unlawful for any person,\nfirm, association or corporation to sell, lease, or offer for sale or\nhire for use in this state any traffic control device unless it conforms\nto the current manual and specifications for a uniform system of\ntraffic-control devices maintained by the department of transportation\nor unless a certificate of approval has been issued by the commissioner\nof transportation.\n