K390 Steel FRN Handle Back Lock Full-Flat Grind K390 is a high-alloy particle metallurgy tool steel enriched with high volumes of vanadium, tungsten and cobalt. Produced by BO?hler-Uddeholm, its advanced alloy composition offers exceptional edge retention and toughness and makes it an ideal choice for steel connoisseurs. This remarkable expression of the Ladybug is the first in a special series of Spyderco knives to supercharge the proven features of well-established models with this elite, high-performance steel. To make these K390-bladed knives even more unique, their injection-molded FRN handles will feature a distinctive blue handle color.table.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }