The Kershaw Leek Knives were designed by custom knife maker and innovator Ken Onion. The Kershaw Leeks have the patented Ken Onion Speed-Safe assisted opening mechanism. Speed-Safe is a torsion bar system that assists the blade to an open position, when activated by a push on the thumb stud, or the Index-Open blade extension. The Kershaw Leek knives are available with stainless steel handles or aluminum handles.