Delaware Code
Part 5. Performance
§ 2-512. Payment by buyer before inspection.

(1) Where the contract requires payment before inspection non-conformity of the goods does not excuse the buyer from so making payment unless
(a) the non-conformity appears without inspection; or
(b) despite tender of the required documents the circumstances would justify injunction against honor under this subtitle (Section 5-109(b)).
(2) Payment pursuant to subsection (1) does not constitute an acceptance of goods or impair the buyer's right to inspect or any of his or her remedies.