- Hydro Grey Titanium, Stonewashed compact EDC folder from the Perez workshop. Blade made of excellent Böhler M390 steel, titanium handle with characteristic diamond texture. Opens with a flipper or hole in the clip. Secure frame lock.

Hydro Grey Titanium, Stonewashed is a compact EDC folder designed by Mark Perez. The blade is made of Böhler M390, considered one of the best knife steels, vacuum-hardened and subjected to a cryogenic stabilization process. This gives the blade exceptional abrasion resistance and long-lasting cutting edge retention. Handle made of titanium with distinctive diamond texture. The frame lock guarantees safety and security during use, eliminating the risk of accidental blade retraction. Ball bearings ensure that the knife opens smoothly and quickly. The titanium clip allows for comfortable tip-up carrying.
Kubey - one of the largest manufacturers producing knives of excellent quality at a great price! The motto of the company is "An Edge Above the Rest". With the use of high-speed CNC machine tools, milling machines, laser cutting or custom hand finishing, the brand focuses on quality workmanship and innovative approaches to design.
M390 Microclean® - a martensitic high-performance chromium steel produced using powder metallurgy. Due to the alloy concept, it is characterized by extremely high wear resistance and high corrosion resistance. Thanks to its high wear resistance, it retains its edge shape, keeping the blade sharp for a very long time (requires minimal maintenance). Another advantage is its resistance to “wire” formation during sharpening. Steel with a high chromium content of 20.0% (Cr) and an admixture of 1.9% carbon (C), 4.0% vanadium (V), hardened to 59-61 HRC. This super steel is comparable to Carpenter's CPM 20CV or CTS-204P steels. Manufactured by Böhler Edelstahl in Kapfenberg, Austria.
Vacuum & Cryogenic - M390 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 converts retained austenite into martensite, significantly increasing hardness, wear resistance and overall durability. Thanks to these advanced processes, M390 steel ensures exceptional performance, offering both razor-sharp edge retention and extraordinary blade durability.
Blade - classic Clip point, finished with a stonewashed finish to hide minor scratches caused during use. The thickness of the blade in combination with the high, flat grind gives excellent cutting edge geometry and extreme cutting performance. Ceramic ball bearings ensure a smooth and easy-running mechanism and support the opening of the blade with a flipper, which, when opened, forms a mini guard to prevent the hand from sliding onto the blade. The knife can also be opened with a hole in the blade. The whole is locked with a proven and popular frame lock with a steel inlay protecting the lock face from wear.
Handle - made of titanium 6AL4V with a characteristic diamond knurling, a material extremely mechanically durable and practically completely resistant to weather conditions and chemicals. The whole is screwed to a solid backspacer, also made of titanium 6AL4V. The simple, solid construction ensures many years of use. The forefinger groove improves grip. 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: KB323A
Product name: Hydro Gray Titanium, Stonewashed M390
Overall length: 185.0 mm / 7.28”
Blade length: 80.0 mm / 3.15”
Blade thickness: 3.1 mm / 0.12”
Handle length: 105.0 mm / 4.13”
Handle thickness: 12.0 mm / 0.47”
Weight: 74.0 g / 2.61 oz
Blade material: Böhler M390
Blade hardness: 60-62 HRC
Blade grinding: Flat
Blade finish: Stonewashed
Handle material: Titanium 6AL4V
Handle finish color: Grey
Backspacer material: Titanium 6AL4V
Backspacer color: Grey
Clip: Right, Tip-Up
Clip material: Titanium
Pivot mechanism: Caged Ceramic Ball Bearing
Locking mechanism: Liner Lock
Opening type: Manual, flipper, thumb hole
Additional accessories: n/a
Designer: Mark Perez
Brand: KB Knives
Manufacturer: Kubey Knife
Country of origin: P.R.C.
Developed by: Sharg® company