'Thread Mill, Helical Flute, Internal Threads, 1/4, Thread Size 1/4 In.-20, Pitch 28 TPI, End Mill Material Carbide, Flutes 3, Length of Cut 0.5140 In., Overall Length 2-1/2 In., TiAlN, Shank Dia. 1/4 In., Thread Type UN, Nomenclature TM, For Use With -, Application All Types of Metals, Composites and Tough-to-Machine Materials'