Priority Mail is used for documents, gifts, merchandise, and any mailable item weighing up to 70 pounds. The maximum size is 108 inches or less in combined length plus girth (distance around the thickest part). Mark each package "Priority Mail" in the postage area when you are not using a USPS-produced Priority Mail envelope or box.
Priority Mail offers 1 day, 2 day, or 3 day service to most domestic destinations. Select Priority Mail packaging is available at the Post Office. All Priority Mail packaging can be ordered online at USPS.com/store or you may use your own packaging. This 1-3 day service may include tracking at no additional cost. Priority Mail bearing an IMpb or retail tracking barcode includes up to $50 of insurance. Additional merchandise insurance up to $5,000 may be purchased for a fee.
Parcels addressed for delivery to zones 1-4 (including local) that weigh less than 20 pounds and measure more than 84" but not more than 108" in combined length plus girth (distance around the thickest part) are charged the 20-pound Priority Mail zoned price.
Parcels addressed for delivery to zones 5-9 that exceed 1 cubic foot (1,728 cubic inches) are charged based on the actual weight or the dimensional weight, whichever is greater.