; or (B) in the case of a gun dealer receiving a subgrant, at the end of the two-year period beginning on the date that the grant was awarded to the State or unit of local government from which the gun dealer received a subgrant. (c) Amounts returned The Director shall return to the general fund of the Treasury any amounts returned under subsection (b). 104. Smart prepaid cards (a) In general In conducting the grant program authorized under section 101, the Director may reserve such funds as may be necessary to acquire and distribute smart prepaid cards to eligible entities that receive grants under this title. The Director shall distribute the smart prepaid cards without any funds loaded onto the cards. (b) Market value of guns The Director shall determine the market value of each gun that the Director determines should be included in the gun buyback program and make such information publicly available. (c) Prohibition on use of cards To buy guns (1) In general A person may not use a smart prepaid card in the acquisition of a gun or ammunition, and a person may not accept a smart prepaid card in the transfer (including a loan) of a gun or ammunition. (2) Penalty A person that violates paragraph (1) shall pay to the Director an amount that is equal to the value of the prohibited sale. 105. Uses of funds (a) States and units of local government A State or unit of local government receiving a grant under this title shall use such funds to do the following: (1) Gun buyback program Use such funds to— (A) conduct a gun buyback program