'Free' DTV converter boxes can't be returned?

Have you read the fine print on your National Telecommunications and Information Administration-issued digital-to-analog converter box program coupon? "You will not be able to receive cash or credit for the coupon amount, but you can receive cash or credit for any amount you paid out of pocket, if the store policy permits." But if you get a defective DTV converter box--or even if you don't like the one you bought--you can take it back for another one, depending on the store's return policy. Of course, the best option to make sure you get a good box the first time.
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