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Carmex Thread Turning Internal Insert - UN (UNC,UNF,UNEF,UNS) - Right Hand - 27IR4.5UNK20

Carmex Thread Turning Internal Insert - UN (UNC,UNF,UNEF,UNS) - Right Hand - 27IR4.5UNK20

SKU:27IR4.5UNK20

The Carmex Thread Turning Internal Insert is a precision cutting insert designed for turning internal threads on right-hand applications. It supports UNC, UNF, UNEF, and UNS standards, making it ... Read more ↓
N
S
Thread TypeInternal
Thread DirectionRight Hand
Thread FormUN (UNC UNF UNEF UNS)
Pitch4.5
Insert Size27
GradeK20
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£16.56
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5 days estimated lead time — subject to availability
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The Carmex Thread Turning Internal Insert is a precision cutting insert designed for turning internal threads on right-hand applications. It supports UNC, UNF, UNEF, and UNS standards, making it a versatile choice for mixed-thread work without needing multiple inserts. Recognized within an industry-leading range, it’s built to deliver dependable performance across a wide range of threading tasks.

These laydown triangular inserts are engineered to provide stable cutting action and smooth chip control, helping you achieve clean, accurate threads with consistent results. Whether you’re tackling simple pilot threads or more demanding production runs, this insert simplifies setup and reduces the need for rework.

  • Broad UNC/UNF/UNEF/UNS compatibility: Turns internal threads across major UN thread standards, minimizing tool changes and keeping your workflow moving.
  • Laydown triangular geometry for stability: Delivers steady engagement, effective chip control, and consistent thread quality across materials and sizes.
  • Proven reliability for demanding applications: Part of an internationally recognized range, engineered for durability and repeatable results in tough threading jobs.

This insert helps you streamline threading operations, reduce setup time, and deliver precise internal threads with fewer passes. Built for reliability and long service life, it supports a broad spectrum of materials and thread sizes, empowering shops to boost throughput while maintaining high-quality results.

Thread Type Internal
Thread Direction Right Hand
Thread Form UN (UNC UNF UNEF UNS)
Pitch 4.5
Insert Size 27
Grade K20

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Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.

We also offer the following:

  • Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
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  • Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
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For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.

*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.

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