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Zoro Select

Zoro Select M50301.180.0024 Copper Sealing Washer M18 25 Pack

SKU CH-FVC4-WSQD2

Copper sealing washers for M18 bolts, 25 pieces with 18 mm inner and 24 mm outer diameter

  • TypeWashers
  • Copper material provides reliable sealing performance
  • Annealed heat treatment ensures consistent washer flexibility
  • 25 washers per pack covers multiple assembly jobs
  • M18 inside diameter fits standard metric bolt sizes
  • 5 mm thickness with ±0.2 mm tolerance guarantees precise fit

Copper M18 Sealing Washers

This 25-pack of Zoro Select copper sealing washers is built for mechanics and technicians who need reliable, single-use seals on M18 fasteners. The plain annealed copper compresses evenly to block fluid or gas leaks in hydraulic, fuel and brake systems. Each washer ships new and ready for immediate installation.

Build fit and clearance

The washers match an 18 mm inside diameter and a 24 mm outside diameter with a uniform 1.5 mm thickness held to a +/- 0.2 mm tolerance. That profile seats cleanly on standard M18 bolt flanges and frees up no extra axial space beyond the nominal thickness. The metric sizing and plain finish suit existing hardware without adapter plates or special tools.

Capacity and limits

Twenty-five pieces cover routine service jobs and small production runs where a copper crush washer is specified. The soft annealed copper yields reliably on first torque but cannot be reused once compressed. Buyers needing larger pack quantities, different bolt sizes or alternative seal materials will need a separate line item.

Highlights

  • Copper material provides reliable sealing performance
  • Annealed heat treatment ensures consistent washer flexibility
  • 25 washers per pack covers multiple assembly jobs
  • M18 inside diameter fits standard metric bolt sizes
  • 5 mm thickness with ±0.2 mm tolerance guarantees precise fit

Specifications

BrandZORO SELECT
TypeWashers

Questions about this item

Will the 1.5 mm thickness compress enough to seal at M18?

The annealed copper is designed to deform under bolt torque; minimum and maximum thickness are both 1.5 mm with a tolerance of ±0.2 mm.

Do these washers get hot or noisy during continuous engine vibration?

Copper washers are passive metal seals; they generate no heat and no noise under normal operating conditions.

What bolt specification must I already have for these washers to fit?

You need a metric M18 bolt or stud; the washer inside diameter is 18 mm and outside diameter is 24 mm.

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