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Zoro Select

Zoro Select ZMBSW-17 Sealing Washer 5/16 in Steel Zinc Plated Pack 5

SKU CH-T1KN-SGCK8

Steel bonded sealing washer with Buna-N seal, zinc-plated finish, 5/16 in bolt size, pack of 5

  • TypeWashers
  • Zinc-plated steel resists corrosion on the job
  • Buna-N seal blocks leaks at the joint
  • 319 in inner diameter fits 5/16 in bolts
  • 11/16 in outer diameter spreads the load
  • Pack of 5 covers multiple fastening points

Zoro Select ZMBSW-17 Sealing Washer Pack

The Zoro Select ZMBSW-17 is a metal bonded sealing washer designed for a 5/16 in bolt size. It suits automotive and general hardware tasks where a reliable seal is required. The pack contains five zinc-plated steel washers. Buyers needing a different bolt size or a larger quantity should look elsewhere.

Thermals Noise and Power Draw

As a passive hardware component, the washer generates no heat, produces no noise and draws no power during use. Its function is to provide a static seal between mating surfaces. There are no thermal, acoustic or electrical characteristics to consider.

Build Quality Connectors and Mounting

Each washer features a steel body with a zinc-plated finish and a black Buna-N seal. The inside diameter is 0.319 in and the outside diameter is 11/16 in. Thickness is 3/32 in. The bonded construction keeps the seal in place during assembly.

Highlights

  • Zinc-plated steel resists corrosion on the job
  • Buna-N seal blocks leaks at the joint
  • 319 in inner diameter fits 5/16 in bolts
  • 11/16 in outer diameter spreads the load
  • Pack of 5 covers multiple fastening points

Specifications

BrandZORO SELECT
TypeWashers

Questions about this item

How do I install the 5/16 in bonded sealing washer without damaging the Buna-N seal?

Place the steel side against the bolt head with the black Buna-N face toward the mating surface; torque to the fastener spec — over-tightening crushes the 3/32 in rubber layer and breaks the seal.

When should I replace the zinc-plated steel washers in a fluid system?

Swap them whenever the joint is broken or if the black Buna-N ring shows cracks, flattening, or corrosion on the 11/16 in OD steel carrier.

What fails first on the 0.319 in ID bonded washer under continuous vibration and pressure cycling?

The Buna-N seal fatigues and loses compression set before the zinc-plated steel carrier yields, letting fluid bypass the 3/32 in thick gasket.

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