The Dayton End Mill Set is a 2-piece set of 4-flute end mills made of cobalt steel with a TiAlN coating for wear resistance. The set includes one 1/4" diameter x 3/4" length end mill and one 1/2" diameter x 1-1/4" length end mill. Both end mills have a 1/2" shank diameter and are center cutting for plunge cuts. They are designed for high speed machining in aluminum, steel, stainless steel, titanium, and other materials. The end mills feature four flutes for efficient chip removal.