Knipex Cobra. Press the button to adjust to the workpiece. Fine adjustment for optimal adaptation to different workpiece sizes and a comfortable grip width. Self-locking on pipes and screws: no slipping on the workpiece and minimal hand force required. Gripping surfaces with specially hardened teeth, tooth hardness approximately 61 HRC: high wear resistance and stable grip. Reliable capture of the hinge pin: no unintentional shifting. Finger protection prevents pinching of the operator's fingers. Capacity for half-moon, capacity in square millimeters, quadrant drive, square capacity, step-shaped square capacity, triangular capacity, clamping range for hexagonal, clamping range for round, clamping range for square.