Milwaukee Tool 49-57-5378 Hex Rethreading Die 3/4-16 Unf

Product Description

The MILWAUKEE TOOL 49-57-5378 is a hex rethreading die designed to restore damaged or corroded external threads to their original specification. Built from carbon steel, this die cuts a 3/4-16 UNF right-hand thread profile and fits a 1-7/16 inch hex drive for use with a standard tap and die wrench or adjustable wrench. At 0.15 pounds and 1/2 inch thick, it is compact enough for use in tight service spaces. Plumbers, pipefitters, mechanics, and field service technicians reach for rethreading dies when a fastener or fitting thread is too damaged to seat a nut or coupling cleanly without chasing the thread first.

This die is suited for repair and maintenance work on threaded fasteners, hydraulic fittings, pneumatic fittings, and mechanical assemblies that use the 3/4-16 UNF thread standard. It is applicable in both residential and commercial service environments wherever fine unified thread restoration is required on bolts, studs, or male-threaded components. The non-adjustable design keeps the thread geometry consistent from pass to pass, reducing the risk of cutting an oversized or tapered profile during rethreading operations.

Key Features

• 3/4-16 UNF right-hand thread profile for fine unified thread restoration
• Carbon steel construction provides hardness suitable for chasing steel and iron fastener threads
• 1-7/16 inch hex drive accepts standard tap wrenches and adjustable wrenches
• 1/2 inch thickness in a compact, non-adjustable design for consistent thread geometry
• Lightweight at 0.15 pounds for easy transport in a field service kit

Compatibility

Designed as an OEM-style replacement rethreading die for use with standard hex-drive tap and die sets that accept 1-7/16 inch hex dies in the Milwaukee series.

Installation Notes

Rethreading dies are typically used by mechanics, plumbers, or pipefitters performing field repairs on damaged male threads. Before use, ensure the workpiece is secure and, where applicable, that the system is depressurized, de-energized, and drained. Apply cutting oil to the die and the workpiece thread before starting to reduce heat and extend die life. Turn the die slowly and back off periodically to clear chips, following standard hand-tap technique.