Milwaukee 4-40 NC Plug Tap

Milwaukee 4-40 NC Plug Tap

The Milwaukee 49-57-5108 4-40 NC Plug Tap is a precision-machined threading tool designed for clean, accurate internal threads in very small coarse-thread applications. Built for durability and control, it features high carbon steel construction and a black oxide coating to resist corrosion and wear. The straight flute design handles general-purpose threading, while the plug style is ideal for through-hole work—helping you cut smooth threads without snapping the tap (which, at this size, is about as fun as it sounds).

Country of Origin
Varies by production batch

Key Features / Specifications

• Model / Part Number: 49-57-5108
• Brand: Milwaukee
• Size / Thread: 4-40 NC (National Coarse)
• Product Type: Plug tap for internal threading
• Material: High Carbon Steel
• Finish: Black Oxide coating for corrosion resistance
• Tap Style: Straight flute for general-purpose threading
• Tap Type: Plug tap designed for through holes
• Shank: Square shank compatible with standard tap handles and wrenches
• Markings: Laser-etched sizing for clear, long-lasting visibility
• Application Materials: Suitable for brass, aluminum, mild steel, and similar metals
• Usage Note: Hand use recommended — not for power tools
• Recommended Use: Best results with cutting fluid

Ideal For

• Creating or repairing very small internal coarse threads
• Through-hole threading in metal materials
• Precision mechanical, electrical, and fine-detail work
• Users needing maximum control and accuracy in small threading applications
• Anyone working with tiny fasteners—where patience is required and forcing it is a guaranteed mistake