patented pushbutton action for fast & firm adjustment directly on the workpiece Cobras have many adjustment positions, ensuring the best fit on all workpieces, 16" Cobra has 21 positions, self-gripping jaw design shaped to eliminate nut-burring the guard prevents operator's fingers from being pinched gripping teeth are specially hardened (approx. 61 HRC) for longer tool life made from chrome vanadium steel, oil-hardened