The Micro 100 16R755 is a 1/4" diameter, 4 flute, carbide thread mill with a TiAlN coating. It has a right hand spiral flute and can cut 60 degree internal threads. The overall length is 2-1/2" and it has a 1/2" shank. This thread mill is made of micro-grain carbide with titanium aluminum nitride coating for wear resistance and heat dissipation. It can machine a wide range of materials including steel, stainless steel, cast iron, aluminum, and more. The 4 flute design provides efficient chip evacuation while milling internal threads. This is a high performance thread mill for cutting strong, precise internal threads in metals.