Cost: $3.00 Service: Provides both a receipt when you mail, plus a signed and dated return postcard when your package has been delivered. Useful when you want to show both the mailing and the delivery of a package. Mail Class: Priority Mail®, Parcel Post® and Media Mail™. May be combined with Delivery Confirmation™ and Insured Mail Form Required: USPS Form 3804. Complete and attach the form above the delivery address and to the left of the postage.