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Carmex Thread Turning External Insert - API 503 - Right Hand - 27ER4API503BMA

Carmex Thread Turning External Insert - API 503 - Right Hand - 27ER4API503BMA

SKU:27ER4API503BMA

Carmex Thread Turning External Insert - API 503 - Right Hand (27ER4API503BMA) is a versatile threading insert optimized for external thread turning. Its laydown triangular geometry is designed to... Read more ↓
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Thread TypeExternal
Thread DirectionRight Hand
Thread FormAPI 503
Pitch4
Insert Size27
GradeBMA
Download Cutting Data
£19.37
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Carmex Thread Turning External Insert - API 503 - Right Hand (27ER4API503BMA) is a versatile threading insert optimized for external thread turning. Its laydown triangular geometry is designed to cover a broad range of thread standards, helping you complete more jobs with fewer inserts and less setup.

Engineered for both professional shops and hobbyist workbenches, this insert delivers reliable, repeatable results—from basic threads to more demanding applications—so you can keep your workflow productive and on schedule.

  • Broad thread compatibility: Covers the majority of thread standards in one tool, reducing the need for frequent insert changes and speeding up setup for mixed jobs.
  • Triangular laydown geometry for stable cutting: The laydown triangle provides solid seating in your holder and delivers smooth chip control, helping you achieve consistent thread profiles across passes.
  • Durable edge geometry for reliable performance: Designed to resist wear and maintain precision over many cycles, delivering repeatable results across a range of materials and feeds.

This insert helps you streamline threading workflows by minimizing tool changes, shaving cycle times, and delivering consistent, accurate external threads. Whether you’re manufacturing parts, performing quick repairs, or stocking a reliable supply in a busy workshop, this Carmex insert offers dependable performance you can trust job after job.

Thread Type External
Thread Direction Right Hand
Thread Form API 503
Pitch 4
Insert Size 27
Grade BMA

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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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