Heli-coil T1185-04C112S 4-40 Unc Threaded Insert SS304 1000pk

Product Description

The HELI-COIL T1185-04C112S is a free running, tangless wire thread insert designed to provide strong, wear-resistant internal threads in parent materials that are soft, damaged, or prone to thread stripping. Manufactured from 304 stainless steel, this insert measures 0.112 inches in overall length and is sized for 4-40 UNC threads with a 1D length-to-diameter ratio. It features a tangless design, eliminating the need for tang break-off after installation and reducing assembly time. The coiled insert expands slightly when driven in, locking into the host bore and creating a finished thread that meets standard fastener tolerances. This item is sold in a pack of 1000 inserts.

Free running inserts are used across aerospace, industrial manufacturing, electronics assembly, and general maintenance applications where a standard-pitch internal thread must be created or restored in a tapped hole. The 4-40 UNC size is common in light-gauge metal components, electronic enclosures, instrument panels, and precision equipment housings. Installation requires a compatible HELI-COIL tap and installation tool sized for 4-40. The tangless configuration is especially practical in high-volume assembly environments and in blind holes where tang retrieval is not feasible.

Key Features

• Tangless design eliminates post-installation tang removal, reducing assembly steps
• 304 stainless steel construction provides corrosion resistance and durability
• 4-40 UNC thread size suits light-gauge and precision component applications
• 0.112 inch overall length with a 1D length-to-diameter ratio
• 2-3/4 free coils deliver consistent thread engagement
• Pack of 1000 inserts supports high-volume production and service use

Compatibility

Designed as an OEM-style free running thread insert for use in any parent material tapped to accept a 4-40 UNC HELI-COIL insert, including aluminum, magnesium, plastics, and other materials requiring thread reinforcement.

Installation Notes

Installation should be performed by a machinist, assembler, or qualified technician using the correct HELI-COIL tap and drive tool for the 4-40 insert size. The parent material must be tapped with the appropriate oversize HELI-COIL tap before the insert is driven in. The tangless design allows installation and removal without a break-off tool, making it suitable for blind holes. Always verify hole depth and thread engagement requirements before installation.