California
Commercial Code – COM § 2316
(2) Subject to subdivision (3), to exclude or modify the implied warranty of merchantability or any part of it the language must mention merchantability and in case of a writing must be conspicuous, and to exclude or modify any implied warranty of fitness the exclusion must be by a writing and conspicuous. Language to exclude all implied warranties of fitness is sufficient if it states, for example, that “There are no warranties which extend beyond the description on the face hereof.”
(3) Notwithstanding subdivision (2)
(a) Unless the circumstances indicate otherwise, all implied warranties are excluded by expressions like “as is,” “with all faults” or other language which in common understanding calls the buyer’s attention to the exclusion of warranties and makes plain that there is no implied warranty; and
(b) When the buyer before entering into the contract has examined the goods or the sample or model as fully as he desired or has refused to examine the goods there is no implied warranty with regard to defects which an examination ought in the circumstances to have revealed to him; and
(c) An implied warranty can also be excluded or modified by course of dealing or course of performance or usage of trade.
(4) Remedies for breach of warranty can be limited in accordance with the provisions of this division on liquidation or limitation of damages and on contractual modification of remedy ( Sections 2718 and 2719 ).