In 1990 Spyderco shook things up by introducing two knives, the Delica and Endura. First of their kind on the market, both folders opened up the knife market to lightweight performance, one-hand open pocketknives that just about everyone could afford. They settled as our top two bestsellers and their improvement hasn't slowed since. Manufactured by Böhler-Uddeholm, K390 MICROCLEAN® is a state-of-the-art cold work tool steel produced by the particle metallurgy process. Its advanced alloy mix was specifically developed to provide the extreme wear resistance and high compressive strength needed in industrial cutting, blanking, and punching operations. Despite its toughness, its exceptionally fine, homogeneous microstructure also makes it readily machinable and easy to heat treat.