American super-steel that is wear resistant, but difficult to sharpen. Unfortunately the low level of toughness means that it can only be hardened to around 56 RC, causing the edge-holding performance to be diminished. CPM-S90V (a.k.a. 420V), similar to Crucible's S60V but designed to be more wear resistant with a very high carbide volume and high vanadium content. Appreciated for extreme edge-holding. S90V was featured in a sprint run of Spyderco's Military in 2004. Since then it has been used in several sprint runs in knives like the Manix 2 and Paramilitary 2. While S90V holds an edge better than S30V, both are usually hardened to about 59–61 RC. CTS-20CP, Carpenter Technology's version of S90V, with slightly reduced chromium. Features incredible wear-resistance and edge-holding, hardened to about 60 RC. CTS-BD1, Carpenter's versions of Gin-1 with improved chemistry. Originally featured in a Mule Team fixed blade. CTS-XHP, made by Carpenter Technology. Often referred to as a stainless version of D2. D2, a high performance tool steel that features outstanding wear resistance. Spyderco uses Crucible's version of D2, which is a powder metallurgy version. CPM-D2 is found in a sprint run version of the Military model. G2, a.k.a. GIN-1 (銀紙１号), a Hitachi-made low cost stainless steel comparable to, but softer than, AUS-8. Generally hardened in the mid to high RC 50s. A tough, corrosion-resistant steel. H-1, a steel which is ideal for marine applications, because it substitutes nitrogen for carbon and thus is completely rust-proof in any normal environment such as salt water exposure, though can still oxidize if exposed to extreme heat and chemical attack. It grinds, scratches and has edge retention similar to the low carbide steels such as AUS-6. It is a precipitation hardening steel, which means it hardens by the mechanical process of grinding the steel, rather than by heat treating. MBS-26, a Japanese [stainless] steel, very fine grained with high corrosion resistance used in the Catcherman and in most kitchen knives by Spyderco. N690CO, an Austrian stainless steel similar to VG-10. Currently found in the Squeak and previously used in Spydercos manufactured by Fox Cutlery. VG-10 (V金10号), a Japanese steel developed for the horticulture industry by Takefu, often hardened around the RC60 range. Reported to have better corrosion resistance but less edge retention than S30V. Appreciated for taking a fine edge, and being easy to sharpen, while still holding an edge well. Used in most of the