Heli-coil T1185-4C250S 1/4-20 Free Running Insert SS304

Product Description

The HELI-COIL T1185-4C250S is a free-running, tangless wire thread insert designed to restore or reinforce internal threads in parent materials subject to wear, stripping, or high-cycle loading. Manufactured from 304 stainless steel, this insert provides a corrosion-resistant threaded repair solution for use in metal fabrication, MRO, and mechanical assembly applications. The insert measures 0.25 inches in overall length and is sized for a 1/4-20 UNC thread - a 1D length-to-diameter ratio suited for thin-section or standard-depth installations. Licensed tradespeople and precision assembly technicians install these inserts using a dedicated installation tool sized to the thread spec.

This insert is applicable to general industrial, MRO, aerospace support, and OEM production environments where a 1/4-20 UNC internal thread must be formed, repaired, or hardened against wear in a base material. The tangless design eliminates the need for tang removal after installation, reducing labor time on production runs and field repair work. It is appropriate for use in aluminum, cast iron, magnesium, plastics, and other materials with inadequate native thread strength. This package contains one insert from a production quantity of 1,000-piece stock, available as a single unit.

Key Features

• Tangless design eliminates post-installation tang removal steps
• 304 stainless steel construction for corrosion and heat resistance
• 1/4-20 UNC thread size for broad compatibility with standard fastener systems
• 1D length-to-diameter ratio suits thin-section parent material applications
• 3-3/8 free coils provide consistent thread engagement and load distribution
• 0.25 inch overall length for compact, flush, or near-flush installations

Compatibility

Designed as an OEM-style free-running thread repair insert for parent materials tapped to accept a 1/4-20 UNC HELI-COIL compatible insert bore.

Installation Notes

Installation requires a correctly sized HELI-COIL compatible insert installation tool matching the 1/4-20 thread specification. The parent material must be drilled and tapped to the manufacturer-specified insert bore diameter before installation. Power down or de-energize any assembly before performing thread repair work in electrical or mechanical systems. Follow applicable facility safety and tooling procedures throughout the repair process.