S.C. Code Ann. § 31-10-40

Upon adoption of an ordinance establishing a commission, the governing body of such municipality shall provide for the governance of such commission by either of the following methods. A commission may be governed by the members of the governing body of its parent municipality serving ex officio or by not less than five nor more than nine commissioners selected by the governing body of the municipality. In the event the governing body initially elects to appoint commissioners to operate the commission, it may at any time in its sole discretion abolish the office of commissioners and assume the direct responsibility for operation of the commission.