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The Penny is an item in the PC release of Mario's Time Machine. It is a form of currency in the United States of America that Mario receives in 1752 (despite the American penny only being manufactured from 1793 onward). It is given to him by a constable in Philadelphia, who asks him to watch the place he is supposed to be looking after while he runs off to take care of a potential crime, and in return, he pays him with the Penny. Mario thanks the constable for giving the Penny to him. He then uses it to pay for a Stamp given to him by Deborah Read at her store (although Deborah gives him the Stamp first, as she believes that Mario is a trustworthy person).