Non-developmental item

Military
A non-developmental item (NDI) is

"Any item that is available in the commercial marketplace; any previously developed item that is in use by a Department or Agency of the United States, a State or local government, or a foreign government with which the United States has a mutual defense cooperation agreement; any item described above, that requires only minor modifications in order to meet the requirements of the procuring Agency; or any item that is currently being produced that does not meet the requirements of definitions above, solely because the item is not yet in use or is not yet available in the commercial market place."