Kershaw Model 1580ST BOA, Design By knife maker Ken Onion. With the new Speed Safe torsion bar technology these knives are very quick to open with just a touch with the index finger or use of the thumb stud . The Blade is made out of CPM-440V stainless steel ti-nitride coated blade hardened to 55-57HRC . Powder coated black aircraft aluminum handles mounted on double heat treated 410 stainless steel liners, with liner lock mechanism and removable pocket clip. Safey lock on top side of the knife to secure lock up in the closed position. Blade length: 3 3/8", Closed length:, 4 3/4", Weight: 4.90 ounces