Jergens 215-066353 Keylocking Thread Insert M8x1.25

Product Description

The JERGENS 215-066353 is a thin wall keylocking thread locking insert designed to create a permanent, wear-resistant internal thread in a parent material. The insert features an M8 x 1.25 internal thread and an M12 x 1.25 external thread, with an overall length of 12 mm. Constructed from 303 stainless steel with a passivated finish, it delivers corrosion resistance in demanding environments. The keylocking design mechanically locks the insert into the host material using keys that are driven into the parent material, preventing rotation and pullout. Licensed HVAC, plumbing, and mechanical contractors as well as maintenance technicians install these inserts where thread repair or reinforcement is required.

This insert is suited for applications where a strong, stable internal thread is needed in softer or previously damaged parent materials. The thin wall profile allows use in situations where minimal material removal is required, making it practical for tight-clearance bores. Metric coarse thread designation follows standard Metric Coarse conventions, and the insert meets NAS 1394 standards. It is appropriate for both original equipment manufacturing applications and field repair scenarios across industrial, commercial, and mechanical maintenance environments.

Key Features

• M8 x 1.25 internal thread with 6H class of fit for precise thread engagement
• M12 x 1.25 external thread with 6G class of fit for controlled installation fit
• Thin wall keylocking design mechanically prevents rotation and axial pullout
• 303 stainless steel construction with passivated finish for corrosion resistance
• Meets NAS 1394 standard for keylocking threaded inserts
• 12 mm overall length suits shallow bore applications where space is limited

Compatibility

Designed as an OEM-style and repair-grade replacement keylocking thread insert for applications requiring an M8 x 1.25 internal thread within an M12 x 1.25 external thread bore, conforming to Metric Coarse thread standards per NAS 1394.

Installation Notes

Installation is typically performed by a machinist or qualified mechanical technician using the appropriate installation tool for keylocking inserts. The parent material bore must be drilled and tapped to the correct M12 x 1.25 specification before the insert is pressed or threaded into position. Keys are then driven flush or below the surface of the parent material to lock the insert against rotation. Power down and de-energize any associated equipment before performing thread repair or insert installation on machinery.