High speed steel or Cobalt; 5 PC. SETS: 1/4, 3/8, 1/2, 3/4 & 1" 60 degrees; HSS For portable and machine work when operated at comparatively high speeds 5 PC. SETS: 1/4, 3/8, 1/2, 3/4 & 1"Single flutes will countersink holes much smaller than multi-flute tools; High speed steel or Cobalt

For portable and machine work when operated at comparatively high speeds Single flutes will countersink holes much smaller than multi-flute tools.