Without prejudice to clause 8.1.1 above, the Supplier undertakes that if the Supplier quotes or offers to a third party lower prices or better terms for System and/or Equipment of the same or similar quality, quantity, or description to the System and/or Equipment (or the items comprised in it) and/or Services, DTN shall be entitled to purchase the System and/or Equipment (or the relevant items comprised in it) and/or Services on the same terms, and where payment for the System and/or Equipment and/or the Services has already been made by DTN, shall be entitled to a refund of the amount of the difference in respect of all such System and/or Equipment supplied after whichever is the earlier of the first quotation or the first supply at the lower price.