Spyderco Endura 4 Redline Black FRN Lightweight Combination

Spyderco was founded in 1976 by Sal and Gail Glesser. They settled in Golden, Colorado in 1978 and initially the company focused on selling its first product: The Tri-Angle Sharpmaker™, which was sold primarily at fairs and trade shows across the country.
In 1981, Spyderco introduced its first closing knife, the C01 Worker. This knife pioneered the concept of a round hole in the blade for one-handed opening, a clip on the handle for top-of-pocket carry, and the option of a serrated or combination blade for aggressive cutting power. These features revolutionized the knife industry and literally defined the shape of the modern closing knife.
Since then, Spyderco has steadily evolved to become one of the leaders in the knife industry. In addition to a worldwide distribution network and manufacturing resources in the US, Japan, Taiwan, Italy and China, their innovations have earned them an impressive portfolio of patents, trademarks and industry awards. More importantly, these innovations have ingrained the trust and loyalty of countless thousands of devoted Spyderco knife users around the world - an audience to whom they are extremely grateful because a satisfied customer is the best advertisement.
For his inventions and his innovative approach, company president Sal Glesser was inducted into the Spyderco Hall of Fame by Blade Magazine.

Spyderco's most famous models:

Spyderco Military
Spyderco Para Military
Spyderco Delica
Spyderco Endura
Spyderco Police
Spyderco Tenacious
Spyderco Native
Spyderco Chaparral
Spyderco Harpy
Spyderco Manix
Spyderco Yojimbo

Steel used:
Spyderco has experimented with different steels over the years. In 1994, Spyderco was the first manufacturer to use powder metallurgy in the form of S60V tool steel.
H-1 steel was developed for knives exposed to salt water and sea air.
154CM American premium stainless steel.
- 8Cr13MoV , Chinese stainless steel tempered to RC56 to RC58, tough and durable, used in Resilience, Grasshopper, Kiwi3 and Byrd series knives. Often compared to AUS-8, but contains slightly more carbon.
- 9Cr18Mo, a higher quality Chinese stainless steel, used primarily in high-end hairdressing scissors and in surgical instruments.
- 440C , a stainless steel known for its corrosion resistance and ease of grinding
- Aogami Super Blue Japanese high-end steel manufactured by Hitachi. "Blue" refers not to the color of the steel itself, but to the color of the paper in which the raw steel is wrapped :-)
- AUS-8 , a frequently used Japanese steel, known for its ability to produce a very fine edge due to its higher vanadium content. Easy to sharpen, corrosion resistant.
- AUS-10 , a Japanese stainless steel series produced by Aichi, with the same carbon content as 440C but containing less chromium.
- D2 , an excellent tool steel, has one percent less chromium than the limit for stainless steels. Spyderco uses a powdered version of D2, CPM-D2.
- H-1 , is ideal for marine use, substituting nitrogen for carbon and is therefore nearly rustproof in any common environment, as well as salt water. It can oxidize if exposed to extremely high temperatures or chemical influences. It has properties similar to low carbon steels.
- CPM SPY27 - Spyderco has long been a leader in the use of exotic, high-performance blade steels. After years of using the best materials the world's leading steel manufacturers could provide, they decided it was time to create their own. Working closely with Crucible® Industries, they developed CPM SPY27 - a stainless particle metallurgy steel containing a proprietary blend of alloys including vanadium, molybdenum, niobium, nitrogen and cobalt.
This remarkable formulation, enhanced by the amplifying effects of cobalt and the state-of-the-art Crucible Particle Metallurgy process, is produced exclusively for Spyderco and will appear in select models manufactured in the USA.
- CPM S30V steel American powdered steel, with a high carbon content, developed specifically for knives.
- CPM-S60V , (440V, CPMT440V) Modern American steel, wear resistant but difficult to sharpen. Unfortunately, the low level of hardness means that it can only be hardened to approximately 56 HRC.
- CPM-S90V (420V), similar to S60V but designed to be durable, with a very high carbon and vanadium content. Valued for its extreme durability. The S90V was used in the 2008 Spyderco Military sprint run. Since then it has been used in several versions of the Spyderco Manix 2.