For letter-size pieces exceeding 3.3 ounces see R600 . Carrier route information updated using CASS-certified process within 90 days before mailing. Mailings consisting of packages claimed at more than one Enhanced Carrier Route rate must bear appropriate marking for rate claimed. For additional marking standards for carrier route pieces, see M014 . See below for tray label Line 2 information.
Additional standards apply to mailings of nonidentical-weight pieces.
For Line 1, use 5-digit destination. 5-digit trays are required if there is enough mail for a full tray, optional otherwise, but preparation of content must be as described. No minimum number of carrier route packages for same 5-digit area. For Line 1, use 5-digit destination. 2 125-piece minimum per route.