DC Velocity--The U.S. Postal Service has rolled out a shipping service it hopes will help it make inroads in markets where its presence up until now has been virtually non-existent.

The service, called "Priority Mail Regional Rate Box," is patterned after the USPS's Priority Mail flat rate offering that lets mailers pay the same rate regardless of how much material they stuff into the box. The new service is geared toward businesses shipping packages weighing between five and 15 pounds for short distances (up to 700 miles) and that need to arrive in two to three days.