




KUNGJUER Helicoil M10x1.25 thread repair insert kit is a complete rethreading solution designed to restore and strengthen damaged M10x1.25 internal threads in engines and machinery.
If a bolt hole has been stripped, cross-threaded, or worn from repeated use, this kit supplies the tools and inserts needed to rebuild the internal thread to a durable, standardized M10x1.25 finish. The set combines precision-manufactured stainless steel inserts with matching drill, tap, installation and break-off tools in a compact iron case so you can repair threads cleanly on the workbench or roadside.
The kit restores stripped threads by enlarging the damaged hole with a purpose ground 135° drill, cutting new threads with the HSS screw tap, and inserting a hardened stainless-steel coil that forms the new load-bearing surface. The coil conforms to bolt dimensions while the install tool seats it to exact depth, and the break-off pin is removed to leave a flush finish.
This M10x1.25 kit is built to work in soft and medium metals commonly found in automotive and mechanical assemblies: aluminum, cast iron, carbon steel, bronze and magnesium. It’s ideal for engine cylinder heads, gearboxes, brackets and any location where thread integrity is critical but base material may be too soft to hold a bolt reliably.
The tooling simplifies each step: the tapered 135° drill clears the old thread cleanly, the precision HSS tap forms accurate new threads, and the ergonomic installation handle seats inserts uniformly. Each insert is manufactured from precision stainless steel for predictable results, and the carry case keeps tools organized so you won’t mix sizes or lose parts during a repair.
The set contains a twist drill, HSS screw tap, installation tool, break-off pin tool, ten M10x1.25 stainless-steel thread inserts, a hex key, and a compact iron storage case. Using inserts instead of oversizing repairs preserves component geometry while providing a stronger, wear-resistant thread that extends service life and reduces the need for repeated repairs.
Who this is for: This KUNGJUER Helicoil M10x1.25 kit is aimed at mechanics, DIY automotive enthusiasts, machine shop technicians and maintenance professionals who need a reliable, portable solution to repair and reinforce internal threads. It’s particularly useful when working on engines, transmissions, mounts or any assembly where restoring standardized bolt threads quickly and durably matters.
Q: Can this kit repair aluminum engine heads?
A: Yes. The M10x1.25 inserts and HSS tap are suited for aluminum and similar soft metals to restore durable threads.
Q: How many repairs can I do with this kit?
A: The kit includes ten M10x1.25 inserts, allowing up to ten full thread restorations if one insert is used per hole.
Free shipping across Canada on every order, with no minimum. Orders are processed within 1 business day and standard delivery across Canada usually takes 2 to 5 business days after processing, with tracking by email. See the shipping policy.
Free 30-day returns. You have 30 days from delivery to start a return. Return shipping is free: email us your order number and we send a prepaid label. See the return & refund policy.
Not sure it fits? Email northtrailauto@gmail.com with your year, make, model and engine and we reply within 1 business day.












