10 U.S.C. § 505 — Regular components: qualifications, term, grade

(a) The Secretary concerned can accept original enlistments in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Regular Coast Guard, as the case can be, of qualified, effective, and able-bodied persons who are at least seventeen years of age nor more than forty-two years of age. However, no person under eighteen years of age can be originally enlisted without the written consent of his parent or guardian, if he has a parent or guardian entitled to his custody and control. (b) A person is enlisted in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Regular Coast Guard in the grade or rating prescribed by the Secretary concerned. (c) The Secretary concerned can accept original enlistments of persons for the duration of their minority or for a period of at least two but no more than eight years, in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Regular Coast Guard, as the case can be. (d) (1) The Secretary concerned can accept a reenlistment in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Regular Coast Guard, as the case can be, for a period determined under this subsection. (2) In the case of a member who has less than 10 years of service in the armed forces as of the day before the first day of the period for which reenlisted, the period for which the member reenlists must be at least two years but no more than eight years. (3) In the case of a member who has at least 10 years of service in the armed forces as of the day before the first day of the period for which reenlisted, the Secretary concerned can accept a reenlistment for either— (A) a specified period of at least two years but no more than eight years; or (B) an unspecified period. (4) No enlisted member is entitled to be reenlisted for a period that would expire before the end of the member’s current enlistment. (e) Enlistments in the Space Force .— For enlistments in the Space Force, see sections 20301 and 20302 of this title.