US First Flight Cover Pan Am Agana, Guam to Iowa City, Iowa via Victoria, Hong Kong 1937 US Scott c21.

This US First Flight Cover was sent from Pan Am Guam to Iowa City via Hong Kong in 1937. The cover features the US Scott c21 stamp with a denomination of 20 cents. It is a used cover with a machine cancel. The cover has a multi-color design and is related to the topic of aviation. The cover is ungraded and uncertified. The cover is a great addition to any stamp collection and is a unique piece of history.