Heli-coil 5403-12 M12 X 1.75 Thread Repair Kit 18 Inserts

Product Description

The HELI-COIL 5403-12 is a complete threaded insert thread repair kit engineered for restoring damaged or stripped M12 x 1.75 metric coarse threads. The kit includes all components needed to complete the repair in the field or shop: a drill, a tap, an installation tool, a tang removal tool, and 18 helical wire inserts. Insert lengths range from 12 millimeters to 24 millimeters, giving the technician flexibility across a range of fastener engagement depths. This kit is used by mechanics, millwrights, and maintenance technicians working on metal components where thread integrity is critical to assembly strength and torque retention.

This kit is suited for metric coarse thread repair applications across automotive, industrial, and general mechanical maintenance work. It covers situations where parent material threads have been cross-threaded, stripped, or otherwise damaged beyond direct re-tapping. The 18 inserts are divided into three length sizes, with 6 inserts per size, allowing multiple repairs from a single kit. The included installation tool part number is 3747-12 and the tap part number is 2087-12, which are standard HELI-COIL accessories used across the product line for M12 applications.

Key Features

• Complete kit includes drill, tap, installation tool, tang removal tool, and 18 wire inserts
• M12 x 1.75 metric coarse thread size for broad compatibility in metric fastener applications
• Three insert lengths covered: 12 mm, 18 mm, and 24 mm with 6 inserts per length
• Tang removal tool size 25/64 included for clean post-installation finishing
• Insert package part number R1084-12 for individual insert reorder reference
• All-in-one format reduces the need to source components separately

Compatibility

Designed for M12 x 1.75 metric coarse threaded applications in ferrous and non-ferrous parent materials where thread repair or thread reinforcement is required.

Installation Notes

Thread repair should be performed by a qualified mechanic or maintenance technician familiar with helical insert installation procedures. Before beginning, ensure the workpiece is fully de-energized or removed from service and properly secured. Use the included drill and tap in sequence before driving the insert to the specified engagement depth with the installation tool. Remove the tang after installation using the included tang removal tool to complete the repair.