CERTIFIEDMAIL
Certified Mail
Certified Mail is a type of Special Service mail offered by the United States Postal Service and other postal services that allows the sender proof of mailing. Some in-transit tracking and delivery confirmation information may be provided, but is not guaranteed with Certified Mail. Certified Mail is only available for Priority Mail and First Class Mail letters mailed within the United States and its territories . Each piece of Certified Mail is assigned a unique label number which serves as an official record of mailing of the item by the Postal Service.The above text is a snippet from Wikipedia: Certified Mail
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