Minimum 5.5 inches 3.5 inches 0.007 inch none Maximum 6 inches 4.25 inches 0.016 inch not applicable Large Envelopes (Flats) Length Height Thickness Weight Minimum 5 inches 3.5 inches 0.007 inch none and at least one dimension 11.5 inches 6.125 inches 0.25 inch meets or exceeds Maximum 15 inches 12 inches 0.75 inches 4 pounds Packages (Small Packets) Length Height Thickness Weight Minimum large enough to accommodate postage, none address, and other required elements on the address side Maximum 24 inches 4 pounds Length plus height plus thickness of 36 inches Rolls Length Length plus Weight twice the diameter Minimum 4 inches 6.75 inches none Maximum 36 inches 42 inches 4 pounds 1125.3 Minimum Volume Requirements Minimum Volume Requirements Letters none Postcards none Large none Envelopes
Minimum 5.5 inches 3.5 inches 0.007 inch none Maximum 6 inches 4.25 inches 0.016 inch not applicable Large Envelopes (Flats) Length Height Thickness Weight Minimum 5 inches 3.5 inches 0.007 inch none and at least one dimension meets or exceeds 11.5 inches 6.125 inches 0.25 inch Maximum 15 inches 12 inches 0.75 inches 4 pounds Packages (Small Packets) Length Height Thickness Weight Minimum large enough to accommodate postage, address, and other required elements on the address side none Maximum 24 inches 4 pounds Length plus height plus thickness of 36 inches Rolls Length Length plus twice the diameter Weight Minimum 4 inches 6.75 inches none Maximum 36 inches 42 inches 4 pounds 1125.3 Minimum Volume Requirements Minimum Volume Requirements Letters none Postcards none Large Envelopes none