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Heli-Coil 554312 M12 x 1.25 Metric Thread Repair Kit

Part of: Heli-Coil Metric Thread Repair Kit

Other options in this family: Heli-Coil 554610 Heli-Coil 554310 Heli-Coil 554412 Heli-Coil 55466 Heli-Coil 55468

Manufacturer

Picture for manufacturer Heli-Coil

Part Number

554312
14 reviews
Sale Price

$64.63

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The Heli-Coil 554312 is a complete metric fine thread repair kit designed to restore damaged or stripped M12 x 1.25 threads in aluminum, magnesium, and cast iron components. This professional-grade kit provides everything needed to create strong, permanent thread repairs that exceed the strength of the original threads.

Kit Contents:

  • M12 x 1.25 Heli-Coil tap for precise thread preparation
  • STI-3 installation tool for proper insert placement
  • Six (6) stainless steel thread inserts, 18mm length (1.5D)
  • Complete installation instructions

Specifications:

  • Thread Size: M12 x 1.25mm (metric fine pitch)
  • Insert Length: 18mm
  • Required Drill Size: 31/64 inch (12.3mm)
  • Tool Type: STI-3 installation tool included

Common Applications:

  • Cylinder head bolt repair
  • Motor mount and bell housing threads
  • Engine and transmission drain plug repair
  • Spark plug hole restoration
  • Oil pan and differential repairs

Heli-Coil thread inserts are the industry standard for permanent thread repair. The coiled wire design distributes stress evenly across all thread flanks, creating a stronger connection than the original tapped hole. Once installed, the insert becomes a permanent part of the parent material and will not back out or loosen over time.

PayPal is great

I was very happy thank you

Hassle-free shopping

Excellent

Great pricing and ability to use coupon code is a plus!

Very Informative

Pretty easy. A+

Correct part in a timely fashion.

Autoplcity got my order shipped quick! I wanted to make sure that it was the right order and they helped me out through chat no problem. They're also centrally located so I suppose shipments to anywhere in the US wouldn't take long at all. They also had a part that I couldn't find anywhere in Salt lake and only few other places on the Internet. None at this good a price. I'm sticking with these guys.

Great price and good company to buy from!

I ordered CV axles from Autoplicity and had them in less than a week! Definitely the best prices for quality product on this item. Will be a return customer for sure!

I was apprehensiveness at first to make a major purchase with Autoplicity due to their extremely low price and lack of reviews. I decided to take the chance and I am very glad I did. I made my order on a Monday morning at 0900 eastern time and my product arrived on Wednesday at 3pm. The item was exactly as described and the most astonishing part is that my purchase was released from the factory less than 45 days ago. I was expecting a model that had been sitting on a shelf for the last year and needed to be updated. That was not the case. I will definitely order from Autoplicity again in the future.

Very good price. Super quick delivery. Will def. buy from them again. Highley recomend them

Sweetest price on this K&N Filter anywhere! Shipped within 24hrs too. I'm coming back to shop for my car next.

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