The Mechanical Part category is available only when the Mechanical calculation model is licensed. This model is based on the Handbook of Reliability Prediction Procedures for Mechanical Equipment, Document No. NSWC-98/LE1. The Mechanical model was developed under the direction of the United States Navy and is the only standard of its kind. It supports failure rate calculations for various mechanical part, including springs, bearings, seals, motors, brakes, clutches, and many more. Regardless of the calculation model selected, when a Mechanical Part category/subcategory combination is selected, the Mechanical model is used for the part. For parameter information for mechanical parts, see Mechanical Model.