Spyderco Endura 4 Folding Knife, K390, FRN Blue, C10FPK390

In 1990 Spyderco shook things up by introducing the Endura. First of its kind on the market, the Endura 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.
We've always taken great pride in our efforts to push the envelope of performance by offering exotic blade steels in our knives. With that spirit in mind, we are proud to offer the Endura 4 Lightweight with a blade crafted from K390.
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.
Collectively, these qualities make K390 an outstanding blade material for true steel connoisseurs.