Machinists Carded Half Round Files, 12 in, Bastard Cut ORS NASCO Upper and lower tongs are Upper and lower tongs are made from a high copper alloy for maximum conductivity and strength Top and bottom tip insulators are a molded fiberglass compound and will withstand intensive heat impact Handles are molded from a durable glass filled nylon material with a good heat and impact resistance Oval point screw cable connection is standard on all models Easy wind drum Easy to read markings Lock ring recoils neatly into contoured case flat on opposite Backs of all half round bastard files are double cut Backs of all 4 and 6" files are single cut Backs of all half round second cut files are longer than 6" are double cut convex and flat surfaces Rounded on one side