VARIABLE PITCH TYPE; STEAM OXIDE FINISH; FERROUS METAL, NON-FERROUS METAL, NON-METALLIC CUT MATERIAL; BI-METAL BLADE MATERIAL; 1-1/4 INCH DIAMETER; 275 RPM (MILD STEEL), 180 RPM (CAST IRON), 360 RPM (BRASS), 410 RPM (ALUMINUM) SPEED RATING