Military handles for letters?

A primary feature of military mail systems is that normally they are subsidized to ensure that military mail posted between duty stations abroad and the home country (or vice versa) does not cost the sender any more than normal domestic mail traffic. In some cases, military personnel in a combat zone may post letters and/or packages to the home country for free, while in others, senders located in a specific overseas area may send military mail to another military recipient, also located in the same overseas area, without charge. Additionally, military postal systems in a host nation may have special agreements with that host nation's postal service allowing military postal customers to send mail to addresses in that host nation at the military's domestic postage rate using their own postage and currency.