E-z Lok 303-6 Thread Locking Insert 3/8-16 Unc Stainless

Product Description

The E-Z LOK 303-6 is a self-locking threaded insert machined from 303-grade stainless steel, designed to create a secure internal thread in pre-tapped parent material. It carries a 3/8-16 internal thread and a 9/16-12 external thread, both to UNC standard, and measures 33/64 inches (0.515 inches) in overall length. The self-lock wall design resists loosening under vibration and dynamic loads without the need for adhesives. Installation requires a standard tap matching the external thread specification. Maintenance technicians, millwrights, and mechanical contractors use these inserts to restore or reinforce threaded connections in metal assemblies.

This insert is suited for applications where a strong, corrosion-resistant internal thread is required in steel, aluminum, or cast components. The 303 stainless steel construction makes it appropriate for environments with moderate moisture or chemical exposure. Typical use cases include equipment repair, fixture fabrication, and thread repair in structural assemblies where the parent material thread has been stripped or requires an upgrade to a finer or coarser pitch.

Key Features

• 3/8-16 internal thread (Class 2B fit) for standard UNC fastener engagement
• 9/16-12 external thread (Class 2A fit) installs with a standard tap - no special tooling required
• Self-lock wall design resists loosening under vibration without adhesives
• 303-grade stainless steel construction offers corrosion resistance and durability
• Bright finish, uncoated surface maintains dimensional accuracy
• Tensile strength rated at 12,651 pounds for high-load applications

Compatibility

Designed for installation in parent material pre-tapped to accept a 9/16-12 UNC external thread, using a standard tap. Suitable for use in steel, aluminum, and similar machinable substrates requiring a 3/8-16 UNC internal thread.

Installation Notes

Installation is performed by a machinist, millwright, or mechanical technician using a standard 9/16-12 UNC tap to prepare the parent material bore. De-energize and lock out any equipment before performing thread repair or insert installation on machinery. Drive the insert to the specified depth using an appropriate insert installation tool to avoid cross-threading or over-driving. Verify thread engagement with a 3/8-16 UNC go/no-go gauge after installation where tolerance is critical.