(c) Qualifications An appointment under subsection (a) or (b) may not be given to an individual until the individual's mental, moral, physical, and professional fitness to perform the duties of an officer has been established under such regulations as the Secretary shall prescribe. (d) Precedence of appointees Appointees under this section shall take precedence in the grade to which appointed in accordance with the dates of their commissions as commissioned officers in such grade. Appointees whose dates of commission are the same shall take precedence with each other as the Secretary shall determine. (e) Inter-Service transfers For inter-service transfers (as described in the Department of Defense Directive 1300.4 (dated December 27, 2006)) the Secretary shall— (1) coordinate with the Secretary of Defense and the Secretary of the Department in which the Coast Guard is operating to promote and streamline inter-service transfers