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Double-Bulb Lid Seals

Series 402 double-bulb seal by Trim-Lok used for marine, auto, or manufacturing applications

About Rubber Lid Seals

What is a rubber lid seal? Lid seals, or rubber bulb seals, are weatherstripping components typically used between your truck bed and truck cap, camper shell or truck lid’s base rail, on watertight doors, skylights, cargo doors, and around windows or anywhere else where noise, dust, moisture, or vibration reduction or elimination is desired. Trim-Lok’s selection of EPDM double-bulb seals and sponge rubber seals are guaranteed to meet or exceed your personal and professional expectations.

How Do Double-Bulb Seals Work?

Rubber double bulb seals consist of two flexible bulb-shaped profiles made of durable EPDM and sponge rubber materials. When a truck cap, window or door is closed, these bulbs compress against the frame, creating a tight seal. This dual-seal design enhances insulation, minimizing air and moisture infiltration, thus improving energy efficiency and preventing drafts. 

The inner bulb usually provides the main seal, while the outer one offers additional protection and resilience. This mechanism helps maintain overall weatherproofing.

Rubber Lid Seals and Foam Seals for a Variety of Uses

Trim-Lok’s comprehensive line of EPDM foam and rubber bulb seal gaskets include durable, double-bulb lid seals for a variety of applications. They have uses in the following industries:

Industries That Use Rubber Bulb Seals

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Double-Bulb Seal Solutions

Our extruded double-bulb lid seals, gaskets, and weatherstrips are used in conjunction with each other to protect cargo and other areas of your vehicle or boat from humidity, water, and other outdoor elements.

Strong, High-Quality Rubber and Foam Lid Seals

Designed by a team of highly skilled and experienced engineers, all Trim-Lok products, including our double-bulb seals, are manufactured using only the highest quality materials available on the market. Available with several tape options, our strongest BT peel-and-stick tape option is a 3M automotive attachment tape that creates a moisture barrier, air-tight seal, and the ultimate bond between the seal and substrate. These high-temperature tapes provide trusted performance and the benefit of resistance to extreme heat.

Why Choose Trim-Lok?

Since 1971, Trim-Lok has been a leading supplier of EPDM rubber seals, including lid seals and double-bulb seals. With easy application and the versatility to be used in an extensive range of applications and environments, our rubber lid seals are sure to meet or exceed your expectations. For more information about Trim-Lok’s line of EPDM foam and rubber seals, contact a local sales representative today.

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Double Bulb Rubber Lid Seal, with a height of .500" and a width of .1.500".


1145 Series Rubber Seal

1145 Series Rubber Seal

Double Bulb Lid EPDM Sponge Rubber Seal, with a height of .550" and a width of 1.500".