E-z Lok 303-820 Thread Locking Insert 1/2-20 Unf

Product Description

The E-Z LOK 303-820 is a self-lock wall thread locking insert designed to provide a secure, threaded connection in materials that require a stronger internal thread than the base material can supply on its own. This insert features a 1/2-20 internal thread and a 3/4-10 external thread, both conforming to UNF standards. Manufactured from grade 303 stainless steel with a bright finish, it delivers corrosion resistance and reliable performance in demanding environments. The overall length is 21/32 inches (0.656 inches). It is installed by machinists, maintenance technicians, and assemblers working in metal fabrication, industrial equipment repair, and precision assembly applications.

This insert is suited for use in metalworking and mechanical assembly where a 1/2-20 UNF internal thread is needed within a tapped 3/4-10 hole. The self-lock wall design resists loosening under vibration and dynamic loads, making it appropriate for both original equipment manufacturing and field repair work. It is commonly specified for light industrial, instrumentation, and mechanical assembly contexts where thread integrity and resistance to rotation are required.

Key Features

• 1/2-20 UNF internal thread with Class 2B fit for standard fastener engagement
• 3/4-10 UNF external thread with Class 2A fit for installation into a standard tapped hole
• Self-lock wall design resists rotation and loosening under vibration
• Grade 303 stainless steel construction provides corrosion resistance
• Bright finish with an overall length of 21/32 inches (0.656 inches)
• Compatible with standard tap type for straightforward installation

Compatibility

Designed as an OEM-style thread repair and thread conversion insert for applications requiring a 1/2-20 UNF internal thread installed into a 3/4-10 tapped hole.

Installation Notes

Installation is typically performed by a machinist or mechanical technician using standard tapping tools. Ensure the receiving hole is tapped to 3/4-10 UNF specifications and is clean and free of debris before driving the insert. Power down and de-energize any equipment before performing thread repair or insert installation on in-service machinery. Follow applicable facility safety and torque procedures for the parent assembly.