<ul>
<li>First-Class Mail International is a generic term for mailpieces that have different shapes, sizes, and contents, that weigh 4 pounds or less, and that are subject to the provisions of the Universal Postal Union Letter-post Convention.</li> 
<li>Items may contain any mailable matter that is not hazardous or prohibited by the destination country. </li>
<li>Aerogrammes are not available for purchase. </li>
<li>Previously purchased aerogrammes are mailable at the applicable First-Class Mail International rate.</li>
</ul> 