This is an
ancillary service for
US Mail that is pretty much
exactly what it says on the tin. It's kind of the cousin of
certified mail for
parcel post,
media mail, or pretty much anything that is a package sent through the
United States Postal Service sent via means other than
first class mail,
express mail, or
priority mail - or rather, mail that is sent via ground routes.
A lot like certified mail, this is a service that provides for tracking of when an item is delivered; unlike certified mail, however, the return receipt is part of the deal.
This service costs $3.