Pieces are eligible if not required to be mailed at First-Class rates or not eligible for Periodicals rates. A certified process must be used at least once a year to ensure accuracy of 5-digit ZIP Codes. See below for tray label Line 2 information.
Additional standards apply to mailings of nonidentical-weight pieces.
For Line 1, use city, state, and 5-digit ZIP Code on mail. For Line 1, use L002, Column A, for destination facility. For Line 1, use L801 for destination facility. Rates are based on tray in which pieces are placed. This guide is an overview only.