"Milwaukee's previous Scissor Shear model 6860 has two blades to create the cutting action. One blade is stationary (48-44-0190) while the other is moveable (48-44-0180). While they can be changed separately, it is recommended that the be changed at the same time for maximum sharpness of cut. The shear is used to cut pliable material such as linoleum, vinyl, carpeting, carpet underlayment and fabric material. Not for use on sheet metal. "