[1-26-20] USPS Retail Ground pieces bearing only postage stamps as postage payment and that weigh more than 10 ounces, or measure more than one half-inch in thickness, may not be deposited into a collection box, Postal Service lobby drop, Postal Service dock, customer mailbox, or other unattended location. These mailpieces are also precluded from pickup service. The sender must present such items to an employee at a retail service counter in a Postal Service facility. Improperly presented items will be returned to the sender for proper entry and acceptance.
