Wis. Stat. § 402.512: Payment by buyer before inspection.

(1) Where the contract requires payment before inspection nonconformity of the goods does not excuse the buyer from so making payment unless:

(a) The nonconformity appears without inspection; or

(b) Despite tender of the required documents the circumstances would justify injunction against honor under s. 405.109 (2).

(2) Payment pursuant to sub. (1) does not constitute an acceptance of goods or impair the buyer’s right to inspect or any remedies available to the buyer.