The Attorney General has considered your request for an opinion wherein you asked, in substance, the following question: Do the provisions of 69 O.S. 633 [69-633](c) (1978) allow a board of county commissioners after having established the best responsible bidder and without further bids to purchase within the current six month period of the materials on which such bidder was established from other suppliers of said materials at the price set out in the journal when the best responsible bidder is unable or unwilling to supply the materials stipulated in the bid and entered in the journal ? 69 O.S. 633 [69-633](c) governs the purchase of materials to construct, reconstruct, or repair by day labor or on a force account basis county highways or any part of the county highway system where the board shall have authority to purchase crushed rock, gravel, sand, cement, hot mix, hot laid asphalt, concrete, steel or other materials in bulk for day to day maintenance of said highways. This section further sets out the procedure to be used in the purchase of said materials. 69 O.S. 633 [69-633] (c) reads in part as follows: and, thereafter, having entered all such bids in its journal and indicated the best responsible bid in such journal, purchases may be made, as needed in accordance with the best responsible bid so entered, without further bids or advertising for said time period above set forth, in any amount; and all requisitions to such best responsible bidder within such period for material of kind, class and character named in the journal as awarded to him shall be deemed to be within the authority granted by this section. It is, therefore, the opinion of the Attorney General that your question be answered in the negative. Where a board of county commissioners has complied with the provisions of 69 O.S. 633 [69-633](c) by advertising for bids on purchases of materials commonly bought in bulk, and has received and accepted the best responsible bids on purchases in excess of $1,500.00, the board may continue to purchase at the same best responsible bid for a period of six months, or not beyond their term of office, on such bid in such amount as may be needed from time to time without further advertising for additional purchases in excess of $1,500.00. When the best responsible bidder is unable or unwilling to supply the materials at the price stipulated in the bid and entered in the journal, the board of county commissioners must again take bids to comply with statutory procedure. (VICTOR G. HILL, JR.) (ksg)