; specialized equipment and training devices; expansion of public and private plants, including ammunition facilities, authorized by section 2854 of title 10, United States Code, and the land necessary therefor, for the foregoing purposes, and such lands and interests therein, may be acquired, and construction prosecuted thereon prior to approval of title; and procurement and installation of equipment, appliances, and machine tools in public and private plants; reserve plant and Government and contractor-owned equipment layaway; and other expenses necessary for the foregoing purposes, $1,564,880,000, to remain available for obligation until September 30, 2021. Other procurement, air force For procurement and modification of equipment (including ground guidance and electronic control equipment, and ground electronic and communication equipment), and supplies, materials, and spare parts therefor, not otherwise provided for; the purchase of passenger motor vehicles for replacement only; lease of passenger motor vehicles; and expansion of public and private plants, Government-owned equipment and installation thereof in such plants, erection of structures, and acquisition of land, for the foregoing purposes, and such lands and interests therein, may be acquired, and construction prosecuted thereon, prior to approval of title; reserve plant and Government and contractor-owned equipment layaway, $20,839,366,000, to remain available for obligation until September 30, 2021. Procurement, Defense-Wide For expenses of activities and agencies of the Department of Defense (other than the military departments) necessary for procurement, production, and modification of equipment, supplies, materials, and spare parts therefor, not otherwise provided for; the purchase of passenger motor vehicles for replacement only