S.C. Code Ann. § 59-71-80: Provision for redemption.

Any bond may be issued with a provision for its redemption prior to its stated maturity at par and accrued interest, plus such redemption premium as may be prescribed by the authorities, but no bond shall be redeemable before maturity unless it contains a statement to that effect. In the proceedings authorizing the issuance of such bonds, provision shall be made specifying the manner of call and the notice thereof that must be given.