Professional cable shears: VDE tested and ideal for electricians Why cable shears should be used to cut cable Due to their design, diagonal cutters are not ideal for cable cutting, for example, because their blades meet at an obtuse angle. By contrast, Knipex cable shears cut using a scissors action, producing a smooth and clean result, because the cable is not crushed, but is cut very smoothly and cleanly. They are therefore excellent for shortening cable, e.g. in house wiring work. For example, they cut NYM-J 3x1.5 mm or NYM-J 5x2.5 mm and all other stranded and finely stranded Cu and Al cables up to 50 mm² professionally. The cable shears should not be used to cut hard wire, however, as their cutting edges have not been designed for this.