From USPS website

41-cent Purple Heart stamp

The Purple Heart stamp went on sale Tuesday marking the 75th anniversary of the Purple Heart medal.

Tuesday retired General Colin Powell awarded two wounded soldiers the Purple Heart medal at Walter Reed Army Medical Center. During the ceremony, the U.S. Postal Service dedicated the 41-cent Purple Heart stamp.

"This stamp is an excellent way to honor the great men and women who are dedicated to serving our nation," Powell said.

This is the third time the Purple Heart stamp has been issued.

Tuesday also marks the 225th anniversary of the Badge of Military Merit, the Purple Heart medal's predecessor.