A product’s service life is its expected lifetime, or the acceptable period of use in service. It is the time that any manufactured item can be expected to be ‘serviceable’ or supported by its manufacturer. Expected service life consists of business policy, using tools and calculations from maintainability and reliability analysis. Service life is a unique commitment made by the item’s manufacturer and is usually specified as a median. Actual service life is the maximal recorded life of a product. Service life is different from a predicted life, or MTTF/MTBF (Mean Time to Failure/Mean Time Between Failures)/MFOP (maintenance-free operating period). Predicted life is useful such that a manufacturer may estimate, by hypothetical modeling and calculation, a general rule for which it will honor warranty claims, or planning for mission fulfillment. The difference between service life and predicted life is most clear when considering mission time and reliability in comparison to MTBF and service life. For example: A missile system can have a mission time of less than one minute, a service life of 20 years, active MTBF of 20 minutes, dormant MTBF of 50 years and a reliability of .999999. A consumer item will have different expectations about service and longevity based upon factors such as use, cost, and quality.