- Sumo Blue Titanium, Stonewashed handy EDC folder designed by Jake Hoback. Massive CPM 20CV steel blade, ergonomic titanium handle. Hidden flipper for opening, intuitive button lock. An excellent everyday tool!
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Sumo Blue Titanium, Stonewashed is a perfectly balanced premium folder designed by the renowned designer Jake Hoback. Its solid CPM 20CV steel blade offers unparalleled corrosion resistance and long-lasting sharpness. The ergonomic 6AL4V titanium handle has been precisely shaped to guarantee a secure grip in any situation. The matte texture of titanium ensures excellent control, and the minimalist design increases durability. The discreetly hidden flipper opening allows the blade to be opened instantly with one hand, while the intuitive button lock stabilizes the blade, eliminating the risk of accidental closure. Every detail has been carefully refined, making this model a reliable tool for everyday tasks. Sumo is a combination of precision, durability and modern functionality in a compact form.
Jake Hoback is a master knife maker who has gained recognition for his precision-crafted knives that combine functionality and aesthetics. His designs, which are characterized by a modern approach to traditional forms, are highly regarded by both collectors and professionals. Hoback, inspired by a passion for mechanics and engineering, began his knife-making adventure at a young age, which allowed him to develop a unique style. His knives, made of the highest quality materials, reflect attention to detail and a deep understanding of users' needs. Thanks to innovative technical solutions and a constant pursuit of excellence, Jake Hoback has become synonymous with reliability and mastery in the world of cutlery.
Kubey - an independent brand and one of the largest manufacturers of high-quality knives at a great price! The company's motto is “An Edge Above the Rest”. Thanks to the use of high-speed CNC machine tools, milling machines, laser cutting and custom manual finishing, the brand focuses on high-quality workmanship and an innovative approach to design. Kubey stands for legendary durability and functionality of knife tools that will last for years!
CPM 20CV – one of the best tool steels, American premium martensitic stainless steel. Produced by US Crucible Industries using the Crucible® Particle Metallurgy (CPM) method. The CPM process produces a very homogeneous, high-quality steel with excellent dimensional stability, grindability and toughness compared to steels produced by conventional methods. Designed to provide better wear resistance while maintaining the highest level of corrosion resistance. This super steel is comparable to Böhler's M390 or Carpenter's CTS-204P. According to some knife manufacturers, 20CV is the best of these three steels in terms of edge retention. It consists of 1.9% carbon (C), 20.0% chromium (Cr), 4.0% vanadium (V), 1.0% molybdenum (Mo) and 0.6% tungsten (W). The high chromium content with a little molybdenum makes 20CV one of the best high-grade corrosion-resistant steels.
Vacuum & Cryogenic - CPM 20CV steel undergoes a specialized heat treatment process involving two key stages. Vacuum Heat Treatment - the steel is hardened in a vacuum environment, which minimizes oxidation and ensures more uniform metal properties. This process increases the strength and structural integrity of the steel. Cryogenic Treatment: After heating, the steel is rapidly cooled to extremely low temperatures, often below -100°C (-148°F). This transformation changes the residual austenite into martensite, significantly increasing the hardness, wear resistance and overall durability. Thanks to these advanced processes, CPM 20CV steel ensures exceptional performance, offering both razor-sharp edge retention and extraordinary blade durability.
Blade - massive, Clip Point, finished with a Stonewashed finish to hide small scratches caused during use. The gently curved cutting edge converges towards the tip of the blade. The blade thickness in combination with the high, flat grind results in an excellent cutting edge geometry and extreme cutting performance. Ceramic ball bearings ensure smooth and easy operation and support the opening of the blade by means of a flipper, pin in the blade or by gravity. The locking mechanism is an intuitive Button Lock.
Handle - grips made of titanium 6AL4V, a material with extremely high mechanical strength and virtually complete resistance to weather conditions and chemicals. The whole is screwed to a solid backspacer, also made of titanium 6AL4V. The simple, solid design ensures many years of use. The forefinger groove improves grip and creates a mini guard to prevent the hand from slipping onto the blade. The pivot axis is decorated with a stylized manufacturer's logo. The single-position (right) titanium deep carry clip allows you to carry the knife discreetly in your pocket in a tip-up position (with the tip of the blade up).
Technical data:
Product number: KB400C
Product name: Sumo Blue Titanium, Stonewashed
Overall length: 184.0 mm / 7.24”
Blade length: 80.0 mm / 3.15”
Blade thickness: 4.0 mm / 0.16”
Handle length: 104.0 mm / 4.09”
Handle thickness: 14.0 mm / 0.55”
Weight: 126.0 g / 4.45 oz
Blade material: CPM 20CV
Blade hardness: 60-62 HRC
Blade grinding: Flat
Blade finish: Stonewashed
Handle material: Titanium 6AL4V
Handle finish color: Blue
Backspacer material: Titanium 6AL4V
Backspacer color: Blue
Clip: Right, Tip-Up
Clip material: Titanium
Pivot mechanism: Caged Ceramic Ball Bearing
Lock: Liner Lock
Opening type: Manual, flipper, thumb stud
Additional accessories: n/a
Designer: Jake Hoback
Brand: KB Knife
Manufacturer: Kubey Knife
Country of origin: P.R.C.
Developed by: Sharg® company