Which USPS mail classification has a maximum weight of 13 ounces?

First-Class Mail is the correct classification with a maximum weight limit of 13 ounces for letters and small parcels. This service is ideally suited for mailing personal correspondence and business communications that require faster delivery than standard mail. It provides reliable service at a reasonable cost and is typically used for sending lightweight items, making it a popular choice among senders needing quick and efficient mail options.

Priority Mail and Express Mail, on the other hand, cater to heavier packages and provide expedited services, which means they have different weight limits and timeframes for delivery. Media Mail is specifically designed for shipping educational materials and media items, thus having different restrictions and pricing structures based on the contents rather than the weight limit in the same way First-Class does.