The Hertel 3/8-16 UNC, 4 Flute Plug Hand Pulley Tap is a precision threading tool designed for creating internal threads in pre-drilled holes. Crafted from high-speed steel with a bright finish, this professional-grade tap ensures durability and optimal cutting performance. The 4-flute design provides excellent chip evacuation while maintaining thread quality. With an H3 thread limit, this tap delivers consistent and accurate threading results. The 6-inch overall length and 0.381-inch shank diameter offer excellent reach and stability during operation. This pulley tap is specifically designed for threading applications where standard taps cannot reach, such as deep recesses or pulley hubs. Manufactured by MSC Industrial under the trusted Hertel brand, this tap is an essential tool for machinists and metalworkers requiring precise threading capabilities.