- self-locking on pipes and nuts: no slipping on the workpiece and low handforce required- gripping surfaces with special hardened teeth, teeth hardness approx. 61 HRC: high wear resistance and stable gripping- box-joint design for high stability due to double guide- robust construction, insensitive to dirt; particularly suitable for outdoor work- guard prevents operators’ fingers being pinched- Chrome vanadium electric steel, forged, oil-hardened