Carmex Thread Mills Solid Carbide - With Through Coolant - Whitworth BSW BSF - 3/8 x 16 - MT7Carmex's Thread Mills Solid Carbide with Through Coolant is a precision threading tool designed for Whitworth threads (BSW BSF) in a compact 3 8" diameter with 16 TPI, mounted on MT7 tooling. Building on the MTB concept, this through bore coolant version optimizes chip evacuation and cooling to boost both performance and tool life in demanding precision work. Size and Thread Form: 3 8" diameter, 16 TPI Whitworth threads (BSW BSF) for accurate,