As prescribed in 247.270-4(d), use the following clause:
INDEFINITE QUANTITIES-FIXED CHARGES (DEC 1991)
The amount of work and services the Contractor may be ordered to furnish shall be the amount the Contracting Officer may order from time to time. In any event, the Government is obligated to compensate the Contractor the monthly lump sum specified in the Schedule entitled Fixed Charges, for each month or portion of a month the contract remains in effect.
(End of clause)