"...will include the word “Medium.” Dimensions, cost and service will remain the same. The dimensions for the Medium — formerly “regular” — Flat Rate Boxes are 11" x 8-1/2" x 5-1/2", similar to a shoe box, and 13-5/8" x 11-7/8" x 3-3/8", similar to a clothing box...."
This Article is From: liteblue.usps.gov
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