E-z Lok TH-004-SV Brass Threaded Insert 4-40 Unc

Product Description

The E-Z LOK TH-004-SV is a single vane tapered hole threaded insert machined from brass, designed to install a durable 4-40 UNC internal thread into plastic components. The tapered hole design allows the insert to be pressed or driven into a pre-drilled hole that transitions from 0.153 inches at the small end to 0.159 inches at the large end. With an overall length of 0.135 inches, an insert diameter of 0.172 inches, and a pilot diameter of 0.157 inches, this insert provides a precise, reliable thread anchor in applications where plastic alone cannot sustain the required clamping force. Minimum wall thickness is 0.093 inches.

This insert is intended for use in plastic substrates across a range of light-duty mechanical assemblies, enclosures, housings, and structural plastic components. It is well suited to applications where repeated fastener engagement is required and the base material cannot sustain thread wear on its own. The single vane geometry drives cleanly into a tapered hole without the need for heat or ultrasonic equipment, making it appropriate for field installation and production assembly environments alike. Installers in HVAC, electrical, and equipment service work will find this insert useful when servicing plastic housings and control enclosures.

Key Features

• 4-40 UNC internal thread for light-duty fastener engagement in plastic
• Tapered hole installation - no heat or ultrasonic equipment required
• Brass construction resists corrosion and provides good thread wear life
• Single vane design locks into host material to resist torque-out and pull-out
• Compact profile: 0.135 inches overall length suits thin-wall plastic sections
• Package quantity of 100 with a minimum order quantity of 1

Compatibility

Designed for installation into plastic material. Requires a tapered hole with a small end diameter of 0.153 inches and a large end diameter of 0.159 inches. Minimum host material wall thickness of 0.093 inches required.

Installation Notes

Install using a press or arbor tool aligned to the tapered hole axis to avoid cocking the insert during seating. The host material must be pre-drilled to the specified tapered hole dimensions before insert installation. Confirm that wall thickness meets or exceeds the 0.093-inch minimum to prevent material cracking. De-energize and lock out any assembly before performing thread insert service on energized enclosures or control components.