An express warranty is an explicit offer made voluntarily by the seller that a product will perform according to particular expectations. The typical express warranty offers specific remedies in the event that the product is defective. Express warranties can be oral or written. Written warranties are covered under the federal Magnuson-Moss Act, which is explained in detail below. If a seller offers an express warranty, the product in question is still covered under implied warranty.
The length of a warranty may be specified, but if it is not, the general rule is that consumers have four years from the date of purchase to enforce a warranty claim. This does not mean that the product must last four years. Rather, it means that if there was a defect in the product at the time of purchase that manifests itself later, the consumer is entitled to some sort of remedy.