The Century Line knives have been especially designed for intense use. They receive a thermal treatment which consists of hardening (heating the blade), subzero (cooling from 50 to -196 degrees), and tempering (increasing the steel elasticity) for a longer and more efficient life. The anatomical and ergonomic handle offers safety during use. Made of polycarbonate and fiberglass, the handle is directly injected on the steel bolster and finished with aluminum rivets. The Century Line has a 25-year warranty . The knives are dishwasher safe.