Jergens 215-065951 Keylocking Thread Insert M5x0.8 M8x1.25

Product Description

The JERGENS 215-065951 is a thin wall keylocking thread locking insert designed to provide permanent, vibration-resistant thread reinforcement in parent material bores. Manufactured from C1215 carbon steel with a zinc phosphate coating, this insert accepts an M5 x 0.8 internal thread and installs into an M8 x 1.25 external thread bore. Overall length is 8 mm. The keylocking design uses keys that are driven into the parent material to lock the insert against rotation, making it suitable for applications where pull-out and torque resistance are critical. Licensed machinists, maintenance technicians, and precision assembly professionals install this type of insert.

This insert is suited for metric coarse thread applications in ferrous and non-ferrous parent materials where a smaller external footprint is required compared to standard wall inserts. The thin wall profile allows use in thinner-section workpieces or tight boss geometries without compromising thread integrity. It is appropriate for both original equipment manufacturing and repair or rework operations across industrial, aerospace-adjacent, and general mechanical assembly environments.

Key Features

• Thin wall keylocking design locks against rotation and pull-out without adhesive
• Internal thread: M5 x 0.8 at 6H class of fit
• External thread: M8 x 1.25 at 6G class of fit
• C1215 carbon steel construction with zinc phosphate coating for corrosion resistance
• Meets NAS 1394 standard
• 8 mm overall length in a compact thin wall profile

Compatibility

Designed as an OEM-style keylocking thread insert for metric coarse thread applications requiring an M8 x 1.25 installation bore and M5 x 0.8 internal thread engagement.

Installation Notes

Installation requires a properly sized and toleranced M8 x 1.25 tapped hole in the parent material. A keylocking insert installation tool is required to seat and key-stake the insert; do not attempt installation with standard driving tools. Ensure the workpiece is secured and free of chips before driving keys. Consult the applicable engineering specification and NAS 1394 requirements for hole preparation, insert seating depth, and key-driving procedure.