us postal first class mail international is one of the most affordable shipping options provided by USPS for international shipments. This service allows businesses and individuals to send letters and packages up to 4 lbs internationally at an economical rate. With this service, customers can enjoy reliable delivery times and an affordable price point. However, it is important to note that the delivery speed may vary depending on the destination. First Class Mail International does not include tracking in many countries, which could be a disadvantage for businesses seeking to monitor shipments more closely. For less time-sensitive deliveries, this can be a viable solution to manage shipping costs.