There are no restrictions as to method of application of the return address; only the requirement that a complete government agency return address be placed above the words official business and penalty statement
An envelope, usually made of a paper product. The face may be plain or preprinted with or without an open or glassine address window. The closure may be a gummed flap or a button and string fastener. When required a smaller envelope may be glued on the right face of the larger envelope. The interior may have a printed opaquing design and/or contain chipboard insert(s). It is designed for mailing correspondence/letters; records, or exposed and developed radiographic film. Excludes envelope, photographic negative; envelope, radiographic film mount, dental; and envelope, transparent.
Classification: Envelopes of paper or paperboard, of a kind used in correspondence
NSN 6645-01-212-5626
NSN 5855-01-096-9294
NSN 6135-01-255-4786
NSN 6610-01-034-0798
NSN 6130-00-549-2607
NSN 5975-01-631-5360
NSN 5990-00-234-9136
NSN 5985-01-441-6411
NSN 5925-01-634-0664
NSN 5915-01-571-1862
NSN 5915-01-463-8413
NSN 6240-01-027-6077