The Uncle Sam Hat is an accessory that was released into Hungry Shark Evolution on the July 1 update. During July 4, it rewarded twice as coins as usual. It takes up the top of the player's shark's head.
The Uncle Sam Hat was a free item during July 4. After that date, it costs 1,776 coins, based on the year the United States of America gained independence.
The Uncle Sam Hat gave the player double gold on the 4th of July. After the 4th of July, the Uncle Sam Hat gave, and still gives, a 5% gold income bonus. Therefore it is inferior to the Witch Hat giving 10% gold increase during non-special days.
The Uncle Sam Hat costs 1776 coins. 1776 was also the year that the Declaration of Independence was adopted, thus making America independent from the British Empire.