What is the weight maximum for PMI medium and large Flat-Rate boxes?

The maximum weight for Priority Mail International (PMI) medium and large Flat-Rate boxes is indeed set at 20 pounds. This weight limit applies regardless of the destination, meaning that when shipping items using these Flat-Rate boxes, no single package can exceed this maximum weight. The Flat-Rate pricing structure is designed to simplify shipping costs by allowing customers to send items at a fixed price, as long as they fit within the specified box size and weight limits.

Understanding these limitations is essential for anyone working in postal services, as it ensures compliance with shipping regulations and helps prevent any delays or issues in package delivery. Knowing these specifics also aids employees in providing accurate information to customers and maintaining efficient postal operations.