If you plan to bring any new, non-U.S.-made articles of value, such as cameras, mp3 players, computers, bicycles, or jewelry that are less than six months old, you should register them with U.S. Customs and Border Protection before departure (CBP Form 4457). Alternately, you can carry your original sales receipts to prove that you purchased them in the U.S. This avoids having to pay a duty upon your return.  Customs regulations vary from country to country; there are usually limitations on liquor, cigarettes, and other goods.

To register your items, download and complete the form available online at and present it with your items to a Customs and Border Patrol Officer at an international airport.