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723 Hazardous Materials Warning Labels

See 325 for information on hazardous materials warning labels. Parcels displaying any of the DOT warning labels shown in Exhibit 325.1 are prohibited because items required to bear those warning labels contain hazardous materials or quantities of hazardous materials that possess too great a risk to be safely handled in the mail. Parcels displaying any of the labels shown in Exhibit 325.2a are permitted to be mailed within specific limits set by the Postal Service and as defined in Chapter 3.