Why Copper Washers Are Still the Go-To Seal for Mechanics

Before bonded washers and rubber seals, there was copper — and even now, it’s still one of the most reliable ways to make a tight seal.

A copper washer might look simple, but it does a clever job. When it’s compressed, the soft copper metal crushes slightly, filling tiny gaps and creating a gas-tight and fluid-tight seal. That’s why you’ll find them used in engines, brake systems, and hydraulic fittings — anywhere a dependable seal under pressure is needed.

Why mechanics still trust copper washers

• Heat resistant: Perfect for use in high-temperature areas like engines or exhaust systems.

• Corrosion resistant: Copper naturally resists rust and degradation over time.

• Single-use for best results: Because they crush when tightened, they’re designed to be replaced each time — guaranteeing a perfect seal every time.

Common uses

• Oil sump plugs and drain bolts

• Banjo bolts in fuel or brake lines

• Hydraulic fittings and brake systems

• General automotive maintenance

At Selo, we stock a full range of metric copper washers, all precision-made and available in single quantities — so whether you’re working on one car or an entire workshop’s worth of projects, you can get exactly what you need without bulk buying.

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