Job Work on Lump sum Basis. The Contractor shall note that unless otherwise stated, the tender is strictly on Job Work on Lump sum Basis and his attention is drawn to the fact that rates for each and every Job should be correct, workable and self- supporting. The quantities in the Part–II of tender approximately indicates the total extent of work but may vary to any extent and may even be omitted thus altering the aggregate value of the contract. Claim in such case shall be entertained on pro rata basis. 13.