Each country has customs regulations that apply to all incoming mail. These may include prohibitions on certain kinds of food or entertainment products. Military units may also have additional restrictions imposed by the unit commanders, such as those on size and weight, to ensure logistics support can handle the mail along with other necessities. The maximum length of a package in any category is 72 inches. In addition, Military ZIP Code™ restrictions may be revised as military units move to different locations. While there are specific restrictions for each five-digit military (APO/FPO) Post Office™ area, generally speaking, it is prohibited to mail the following:
· Aerosol cans
· Firearms
· Flammable materials
· Liquids and powders
· Lottery tickets
· Poisons
· Alcohol and liquor
· Ammunition
· Drug paraphernalia
· Fireworks and other explosives