Carmex Thread Mills Solid Carbide - Internal Thread - UN (UNC UNF UNEF UNS) - 1/4 x 28 - MT7Carmex MT7 Solid Carbide Internal Thread Mills are engineered for precise, efficient internal threading in UN forms (UNC, UNF, UNEF, UNS). Designed for professional machinists and job shops, this tool delivers reliable 1 4" 28 threads with a focus on performance and value. Tool type: Solid carbide internal thread mill designed specifically for milling internal threads rather than tapping. Thread forms: Compatible with UN threading standardsUNC, UNF,