Attached Letters Occasionally,  a  parcel  may  be  presented  for mailing at the Standard Mail (B) rate with a letter or other First-Class Mail attached. This is legal as long as the envelope is placed on the address side of the parcel. The name and the address of the sender and the name and address of the addressee should be placed on both the  parcel  and  the  envelope.    If  both  names  and addresses do not appear on both pieces, the sender’s name and address must be placed on either the parcel or envelope and the name and address of the addressee must  be  placed  on  the  other  piece  (see  figure  4-7). Postage  at  the  First-Class  rate  must  be  paid  for  and affixed to the attached letter.   The attached envelope may be marked First-Class. Enclosed Letters Normally, when mail of a higher class is enclosed with mail of a lower class, the rate of postage charged for the entire piece or parcel is that of the higher class. However, letters (First-Class Mail) may be enclosed in Standard  Mail  (B)  parcels  subject  to  the  following conditions:    Postage at the First-Class rate must be paid for each letter.    The letter(s) is/are placed on top of other items in the parcel when practical.    The  total  amount  of  postage  for  each  letter  is placed on the outside of the parcel. The postage for the letter(s) may be added to that of the parcel and the total amount paid together, or the postage for the letter(s) may be affixed separately from the  postage  for  the  parcel. The  endorsement FIRST-CLASS MAIL ENCLOSED must be placed on the parcel below the postage and above the address. SPACE AVAILABLE MAIL (SAM) Parcels  mailed  at  the  surface  postage  rates,  are airlifted  to,  from,  or  between  overseas  military  post offices outside the 48 contiguous states.  These parcels must be marked “SAM” on the address side, below the postage  and  above  the  addressee’s  name. These maximum weight and size limits apply when mailed from: 4-14 PCf0406 Able B. Seaman USS Underway (CV-66) FPO AE 09561-0001 SAM STANDARD MAIL (B) DATE Mr. Jack Frost 5 Sunnyside St. Anytown US 11111 Figure 4-6—Endorsement on a Standard Mail (B) article. PCf0407 NAME AND ADDRESS OF ADDRESSEE SENDER'S NAME AND ADDRESS STAMPS ON PARCEL LETTER POSTAGE ON ENVELOPE Figure 4-7.—How to affix a First-Class letter to a parcel.