A more thorough explanation:

A warranty of fitness is a type of guarantee that ensures that the goods purchased are suitable for the specific purpose intended by the buyer. This warranty is not satisfied by mere fitness for general purposes. It means that the product must be fit for a particular purpose, even if it is fit for its ordinary purpose.

For example, if a person buys a bicycle for racing, the warranty of fitness ensures that the bicycle is suitable for racing and not just for general use. This warranty applies to retailers, distributors, and manufacturers.

An implied warranty of fitness for a particular purpose applies when the seller, at the time of contracting, has reason to know of any particular purpose for which the goods are required, and the buyer is relying on the seller's skill or judgment to select or furnish suitable goods. This warranty may be waived by the buyer if they are an expert or bring in outside experts.

For instance, in Keith v. Buchanan, the plaintiff bought a boat from the defendant for the particular purpose of being "seaworthy." Because the plaintiff's friend, who was experienced with boats, examined the boat before the purchase, the court found that the plaintiff had waived his implied warranty of fitness for a particular purpose.