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Forty small black rubber washers in a pack

PATIKIL M3 Rubber Flat Washer 40 Pack 3mm ID 8mm OD 3mm Thick Black

SKU CH-K9DA-G2PTM

Pack of 40 black rubber flat washers with 3 mm inner diameter, 8 mm outer diameter and 3 mm thickness for sealing and cushioning bolted joints

  • Key featuresFlat, Flat, Rubber, Black
  • Overall height3 mm
  • Overall width1 L x 6.1 W x 10.4 H centimeters
  • Overall length1 L x 6.1 W x 10.4 H centimeters
  • Seals water, oil and air reliably with flexible rubber material
  • Cushions fasteners to reduce pressure and friction on bolted joints
  • Protects nylon and glass surfaces from tearing during tightening
  • 40 washers cover multiple household and plumbing repair tasks
  • 3 mm inner diameter fits M3 bolts precisely

M3 Rubber Flat Washer 40 Pack

This pack contains forty black rubber flat washers sized for M3 fasteners. Each washer has a 3 mm inner diameter and an 8 mm outer diameter with a 3 mm thickness. They suit DIYers and maintenance workers who need reliable sealing or cushioning for bolted connections in household appliances and plumbing fixtures.

Sealing performance in water oil and air

The flexible rubber material resists high temperatures wear and corrosion while providing strong sealing and insulation. It conforms to harder or irregular surfaces to prevent leaks in water oil and air systems. The washers also reduce pressure and friction while increasing the contact area for fasteners.

Fits M3 bolts and protects delicate surfaces

Place a washer between the bolt and the component then tighten to create a seal or cushion. The 3 mm inner diameter matches standard M3 threads and the 8 mm outer diameter spreads the load. They are especially useful when securing nylon or glass parts to avoid surface damage.

How it compares

Measured against everything we stock in Parts Washers & Ultrasonic Cleaners, at today’s prices. Recalculated every night.

Price $9.99
Cheaper than about 90% of the 25 comparable items (median $15.99).

Specifications

Product
Brand namePATIKIL
Size & build
Overall height3 mm
Overall width1 L x 6.1 W x 10.4 H centimeters
Overall length1 L x 6.1 W x 10.4 H centimeters

Questions about this item

How do I install the 3 mm ID rubber washer on an M3 bolt, and what is the common mistake?

Place the washer between the bolt head or nut and the mating surface, then tighten. The common mistake is choosing a washer with the wrong inner diameter, which prevents proper sealing.

What maintenance or replacement will the 40 rubber washers need over time?

Inspect washers periodically for cracking, hardening, or loss of elasticity caused by heat, oil, or UV exposure. Replace any that no longer compress fully or show visible degradation.

What limit appears first when these washers are under sustained compression and temperature?

The rubber gradually loses elasticity and takes a permanent set, reducing sealing force. This compression set is the first limit that degrades performance in long-term use.

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