Speed Tiger Micrograin Carbide Square End Mill - 4 Flute - Ise3/16 4T (5 Pieces, ? APPLICATION - Our carbide tools are highly effective at machining various types of steel such as Carbon Steels (~HB225), Alloy Steels (HB225~325), Pre-hardened Steels (up to HRC45), Hardened Steels (HRC40~56), and Cast Iron. ? AlTiBN COATING - This coating, made of titanium aluminum boron nitride (AlTiBN), offers exceptional stability at high temperatures and surpasses the heat resistance of TiAlN, TiN, or TiCN coatings. ? HIGH-PERFORMANCE MATERIAL - This end mill is made from micrograin carbide, which gives it exceptional toughness, durability, and machinability. It performs brilliantly and is an excellent value for its price. ? FINE WORKMANSHIP - Our products deliver outstanding high accuracy with an error of -0.02mm, empowering users to achieve professional cutting quality effortlessly. ? DEDICATED SUPPORT - Please don't hesitate to contact us on Amazon if you need the Cutting Condition Data. We want to ensure you receive the best product that meets your requirements.