Conn. Gen. Stat. § 12-409a
Sec. 12-409a. Direct payment permits.
(b) Acceptance of certificate. The acceptance in good faith by any vendor of a certificate from a direct payment permit holder stating that he is in possession of a valid direct payment permit shall relieve such vendor of any obligation to collect the sales tax from the permit holder. Such certificate shall be signed by and bear the name, address and registration number of the permit holder.