Close Menu
Sealing Solutions

Get a Reliable Seal Every Time

The Lee Company is the original inventor of the technology that is the undisputed industry standard for reliable sealing of machined holes in any manifold or housing. We offer the broadest range of options to handle an endless combination of materials, pressures, temperatures, and environments. As a result, you can trust Lee products to handle even the most complex applications.

Why Our Sealing Solutions

Proven Solutions for Complex Problems

Lee products have remained the best and most reliable assets in service for decades. Economical, easy-to-use solutions come in various sizes, materials, and configurations for your applications.

Superior Reliability & Performance
Highly engineered single-use products offer superior performance controlled by precision manufacturing processes and exhaustive sample testing. Our process produces proven, field-tested solutions. As a result, hundreds of millions of Lee products have operated for decades without failure.
More Than 75 Years of Experience
The Lee Company engineers have unparalleled experience solving complex customer problems for more than seven decades. So, when you need precision components in mission-critical applications, trust Lee products for long-lasting results.
Ready-to-Go and Custom Solutions
We have commercially available, in-stock, and affordable sealing solutions with hundreds of design options in a range of diameters, lengths, and materials — all ready to use today. Need a custom solution? Our engineers can do that, too.

Sealing Passages in Metal Manifolds

Rather than performing costly welding or installing ball plugs with excessive installation forces, you can use expansion plugs to seal cross-drilled holes and machined passageways in metal manifolds. With a guaranteed helium leak-tight seal, you do not need O-rings or other sealants that may degrade over time.

As the original inventor of expansion plug technology and with hundreds of millions proven in service in every conceivable environment, trust The Lee Company to provide the right solutions for your application.

View Lee expansion plugs in a variety of sizes, materials, and configurations for a wide range of end uses.

Removable and Reusable Sealing

When you need to seal machined passageways that require removable and reusable access for maintenance or repair, Axial Force Only (AFO®) Plugs provide a leak-tight seal that can accommodate high pressure and high-temperature manifold applications.

The plugs have a simple threaded installation, guarantee a helium leak-tight metal-to-metal seal, and are capable of burst pressures up to 56,000 psi and temperatures up to 600°F.

View our line of AFO plugs in a variety of materials, diameters, and maximum proof pressure.

Sealing Holes in Metal Castings or Hard Plastic Manifolds

Do you need to control expansion for your thin-wall conditions or brittle materials? Our tapered expansion plugs are designed to guarantee helium leak-tight seals without the need for O-rings or sealants that degrade over time. Designed for high-volume applications, they are optimized for automated installation and have been field-proven in automotive, industrial, and medical applications.

View our plug solutions for sealing holes in metal castings or hard plastic manifolds in a variety of diameters.

Talk to a Lee Sales Engineer

Technical Knowledge and Industry-Leading Insight

Our degreed sales engineers are ready to work with you directly, providing industry specific knowledge and experience to help solve complex application problems

Support & Resources

Support & Resources from a Team that Speaks Your Language

Partner with The Lee Company and get much more than just a supplier of top-quality fluid control products. Our reliable technical support team is available every step of the way to help you find solutions, maximize productivity, and drive efficiency across your operations. Check out these sealing solutions to learn more.

Innovative Solutions

Lee Expansion Plugs

Over 100 million Lee Plugs have been used on aircraft, missiles, spacecraft, and other sophisticated hydraulic systems requiring a permanent leak-tight seal.