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Zoro Select

Zoro Select M50301.125.0020 Sealing Washer M12.5 Copper 50 Pack

SKU CH-Y88M-Z8T41

Copper sealing washers for M12.5 bolts, 12.5 mm inner diameter, 20 mm outer diameter, 1.5 mm thick, pack of 50

  • TypeWashers
  • Copper construction resists corrosion in fluid systems
  • 5 mm inner diameter fits M12.5 bolts precisely
  • 5 mm uniform thickness ensures consistent sealing
  • 20 mm outer diameter distributes load evenly
  • 50-piece pack covers multiple assembly jobs

Copper sealing washers for M12.5 bolts

These copper sealing washers fit M12.5 bolts and come in a pack of fifty. Each washer has an inside diameter of 12.5 mm and an outside diameter of 20 mm. The plain finish and annealed heat treatment suit general-purpose sealing tasks. The thickness is 1.5 mm with a tolerance of +/- 0.2 mm.

Automotive and industrial maintenance crews

Mechanics and maintenance teams who need a reliable copper seal on M12.5 fasteners will find this quantity convenient. Buyers who require a different bolt size, a different material such as aluminium or fibre, or a larger pack should look elsewhere.

1.5 mm thickness with +/- 0.2 mm tolerance

The uniform 1.5 mm thickness and tight tolerance determine whether the washer compresses correctly in your joint. Verify this dimension against your flange design before ordering.

Highlights

  • Copper construction resists corrosion in fluid systems
  • 5 mm inner diameter fits M12.5 bolts precisely
  • 5 mm uniform thickness ensures consistent sealing
  • 20 mm outer diameter distributes load evenly
  • 50-piece pack covers multiple assembly jobs

Specifications

BrandZORO SELECT
TypeWashers

Questions about this item

How can I verify the washers are sealing correctly after installation?

Check that each copper washer compresses evenly around the M12.5 bolt with no visible gaps; the 1.5 mm thickness should flatten slightly under torque to form a uniform seal.

What comes in the box and what must I source separately?

The pack contains 50 copper sealing washers with 12.5 mm inside diameter, 20 mm outside diameter and 1.5 mm thickness; bolts, nuts and thread sealant are not included.

Which version should I choose for an M12.5 metric bolt?

This single variant is made for M12.5 fasteners with a 12.5 mm bore, 20 mm outer diameter and 1.5 mm thickness — select it when those exact dimensions match your hardware.

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