Gaskets and Seals› O-rings, Grommets and Vacuum Caps
Helicoil
5/16-18 INSERTS/PK 12
SKU: H01G R1185-5
Moderate — 2–4 hours
Description
Each insert measures 0.4690 inches in length and features a 5/16"-18 UNC thread. They are suitable for applications requiring a tensile strength between 200,000 to 250,000 PSI and a Rockwell hardness of C43-C50. The recommended tap size is 5/16"-18 STI, with a corresponding drill size of 17/32".
Fitment
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Specifications
| Brand | Helicoil |
| Part Number | H01G R1185-5 |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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