Publication 2 - Packaging for Mailing - Postal Explorer - USPS.com

Bulk Mail Center Standards6-3.4.26-3.2.2 ClosingThe mailing container must be securely closed with staples, heat sealing,adhesive, or tape. A container without inner packing or a container with loosematerial should be reinforced with reinforced paper or plastic tape,pressure-sensitive filament tape, or firmly applied nonmetallic banding.6-3.3 High-Density Items From 20 to 45 Pounds6-3.3.1 PackingA mailing of high-density items weighing from 20 to 45 pounds must bepacked in at least a 200-pound test fiberboard box or an equivalent wood,metal, or plastic container. A hard nonfiberboard container must be preparedso that its coefficient of friction is similar to that of a domestic-class fiberboardbox of the same size and weight.Internal blocking and bracing must be used as required (methods includeinterior containers, cut forms, partitions, dunnage, and liners). The mailingcontainer must maintain its integrity without damage to its contents if droppedonce from a height of 3 feet on its smallest side onto a solid surface.6-3.3.2 ClosingThe mailing container must be securely closed with staples, heat sealing,adhesive, or tape. A container without inner packing or a container with loosematerial should be reinforced with pressure-sensitive filament tape or firmlyapplied nonmetallic banding.6-3.4 High-Density Items From 45 to 70 Pounds6-3.4.1 PackingA mailing of high-density items weighing from 45 to 70 pounds must bepacked in at least a 275-pound test fiberboard box or an equivalent wood,metal, or plastic container. A hard nonfiberboard container must be preparedso that its coefficient of friction is similar to that of a domestic-class fiberboardbox of the same size and weight.Internal blocking and bracing must be used as required (methods includeinterior containers, cut forms, partitions, dunnage, and liners). The mailingcontainer must maintain its integrity without damage to its contents if droppedonce from a height of 3 feet on its smallest side onto a solid surface.6-3.4.2 ClosingThe mailing container must be securely closed with staples, heat sealing,adhesive, or tape. A container without inner packing or a container with loosematerial should be reinforced with pressure-sensitive filament tape or tightnonmetallic banding.Publication 2, January 200227