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Two small metal back caps for TIG torch, medium size, brushed finish

Miller - Weldcraft

Miller - Weldcraft 300M Back Cap PK2 welding

SKU CH-26K8-BJ4FJ

Pack of two medium back caps for Miller 17, 18 and 26 series TIG torches

  • TypeTools
  • Compatible with Series 17, 18 and 26 torches
  • Fits WP-17, WP-18 and WP-26 models
  • Medium back cap for standard welding access
  • Supplied as a pack of two caps
  • New condition, ready for immediate workshop use

Miller Weldcraft 300M Back Cap PK2

The Miller Weldcraft 300M Back Cap PK2 is a medium-size replacement component for TIG welding torches. It fits Weldcraft Series 17, 18 and 26 torches as well as compatible A-150, A-200, A-250, W-350, W-400 and W-410 models. Professional welders and maintenance teams use it to restore secure electrode retention on worn torches.

Pack of two caps

The PK2 pack supplies two identical medium back caps so a spare is immediately available during a job. Having a matched pair reduces downtime when a cap is lost or damaged on site. No additional tools, adapters or software are included with the package.

Medium designation limits compatibility

The medium size designation means the cap only fits torches designed for that specific length and thread pattern. It will not work with small or large back-cap variants used on other torch series. California Proposition 65 warnings apply because the product contains listed chemicals.

Highlights

  • Compatible with Series 17, 18 and 26 torches
  • Fits WP-17, WP-18 and WP-26 models
  • Medium back cap for standard welding access
  • Supplied as a pack of two caps
  • New condition, ready for immediate workshop use

Specifications

BrandMILLER ELECTRIC
TypeTools

Questions about this item

When will the 300M back cap need replacing on a WP-17 torch?

The back cap is a consumable part; replace it when the threads strip, the O-ring seat cracks or the cap no longer seals the torch head.

What fails first on the 300M back cap during long welding sessions?

Heat cycling fatigues the O-ring groove and threads, so the seal goes before the cap body itself.

Does the 300M back cap get too hot to handle on a WP-26 running all day?

The cap sits at the torch rear and stays near ambient temperature; only the torch head and nozzle become hot during continuous use.

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