The Micro 100 16R681 is a 1/2" diameter, 4 flute, carbide thread mill with a TiAlN coating. It has a right hand spiral flute design and can cut 60 degree internal threads in steel, stainless steel, cast iron, aluminum, and other materials. The thread mill has a shank diameter of 3/8" and an overall length of 2-1/2". It is capable of cutting unified thread sizes from 4-56 to 1"-8 as well as metric thread sizes from M3 to M24. The thread mill should be run at speeds from 100 to 500 SFM depending on the material being threaded. Proper coolant should be used when operating this mill.