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Surcharge Information

Due to the UK’s mostly commonly recognised surcharge mechanism no longer being openly published to the UK market we are unable to provide specific surcharge information on our website at this stage.

We are currently working with our suppliers to establish alternative mechanisms in order to provide a comprehensive and transparent view of global surcharge variations.

Look out for our improved surcharge pages appearing in the coming weeks.


665M17 grade steel is a medium alloy nickel-molybdenum case-hardening steel which may be carburised and hardened to produce a hard wear resistant case developing a core strength of 770N/mm.

It has good impact properties, very good resistance to stock and freedom from temper brittleness.

Size Range

60mm - 250mm Dia

Typical applications of 665M17 grade steel

  • Gears
  • Shafts
  • Pinions
  • Tappets
  • Valve rockers
  • Collets
  • Track pins
  • Steering balls and worms
  • Transmission components
  • Breech mechanisms
  • Small arms parts

665M17 steel is still often referred to as EN34 steel - its equivalent grade under the previous BS 970: 1955 standard.

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Rolled or Forged


Black Bar or Bright Bar

Grades for Potential Substitution (Greater)