Okla. Stat. tit. 69, § 69-634: Bond of contractor

The board of county commissioners shall require each contractor

to furnish a bond pursuant to the provisions of Section 1 of Title

61 of the Oklahoma Statutes but made payable to the county. If the

contractor fails to comply with the terms of the contract, the bond

shall be forfeited to the county treasurer for credit to the county

highway fund. Unless otherwise provided for by contract, the surety

on any bond shall be held, to consent without notice to:

1. an extension of time given to the contractor to perform the

contract if each extension does not exceed sixty (60) days; and

2. any change in the plans, specifications, or contract if such

change does not involve an increase of more than twenty percent

(20%) of the total contract price. If such increase is more than

twenty percent (20%) of the total contractprice, the surety shall be

released only as to such increase in price that is in excess of a

twenty percent (20%) increase.