PS Form 3816 {Ans: COD Mailing and Delivery receipt}Domestic Mail {Ans: Mail sent within the US, APO/FPO, the UN, and all US territories and possesions.}Shipping services {Ans: The services that USPS has competition for in the marketplace. Includes Priority Mail Express and Express flat rate, Priority Mail and Priority flat rate, Parcel select and parcel return services, and International Mail}AVSEC {Ans: Aviation Security}Label 500 {Ans: COD First class mail tracer label used to internally track COD remittance}PS Form 3831 {Ans: Receipt for articles damaged in the mail}