Your LEER fiberglass truck cap or tonneau is a fascinating combination of art, science and technology. Here’s a description of how it is made.

Precise molds are a critical ingredient

Extraordinarily accurate molds are fabricated, using computer-aided design and skilled hand-craftsmanship by the LEER mold shop before being released to the production teams at the three LEER plants (in Elkhart, Indiana; Milton, Pennsylvania; and Woodland, California). While molds may last for years, they also require constant maintenance to keep their mirror-finish surfaces and dimensional accuracy. Literally hundreds of molds are maintained by LEER, and each mold is inspected, cleaned, waxed, polished, and prepped each and every time it is used.

The first element in the mold gelcoat

The first layer in the prepared mold for your cap or tonneau is a gelcoat, a synthetic polymer designed to flow smoothly into every part of the mold. The gelcoat is a thin (2-3 mils) but durable layer that will form the smooth-finished outside surface of your cap or tonneau. It is the gelcoat that will be prepped for painting and will receive the exterior paint finish you see. Because it is directly under the painted surface, LEER gelcoat comes in three colors (white, light grey and dark grey), designed to provide the best coverage, based on the color of paint that will be used.

The key structural component Random strand fiberglass

The next step adds random-strand fiberglass, the key structural component. Long, thin filaments of glass fibers are chopped to lengths averaging 1 to 2 inches long, and are combined with resin (another advanced polymer plastic) and a catalyst that enables the combined ingredients to harden and cure. This layer of chopped glass and resin is applied by skilled operators who control the thickness of the application to within a few hundredths of an inch. If the fiberglass layer is too thick, it is too heavy and too rigid; too thin and it won't have the required strength.

Hand rolling of the fiberglass eliminates air bubbles and voids

While the combination of glass and resin is still curing, it is meticulously rolled out by hand to eliminate any air that may be trapped in the fiberglass layer. At this time, reinforcements of marine grade plywood and metal are added to the mold, where they will be encased in another layer of glass and resin. These reinforcements make it possible for LEER to add racks, lock hardware, hinges, storage boxes, and other bolted-on parts that would otherwise stress the fiberglass.

A lightweight but resilient reinforcement layer is added

A layer of "tri-cel" honeycomb or striated fiber is added at this time. When in contact with resin, this internal stiffener provides an incredibly hard, durable, and resilient layer of reinforcement that adds significant strength with minimum weight to the roof area of the cap or tonneau.

Additional fiberglass is hand laid in dramatic curves and complex shapes

Also, depending upon the design, additional fiberglass is added in the form of hand-laid sheets of "woven roving." This application further strengthens areas of the cap or tonneau that have dramatic curves and complex shapes. Each step of the way, each layer of fiberglass and resin is rolled out to ensure there are no air voids in the structure.

Catalyst hardens and cures the fiberglass

With the fiberglass and reinforcing work complete, caps and tonneaus are set aside so the curing process generated by the catalyst can continue. Soon after it is complete, the new caps and tonneaus are released from the molds and excess material is trimmed off.

Critical eyes inspect every piece fiberglass rails are added to caps

Each fresh part is individually inspected by experienced eyes, and any surface flaws in the molded part are noted and corrected. Caps go through yet another round of fiberglass production, where the fiberglass rails that mount to your truck bed are molded and mated to the caps, using additional hand-applied layers of fiberglass and resin. Caps and tonneaus are mounted on individual shipping boards so they can move through the assembly process with minimal handling.

Painting adding gorgeous color

Inspections continue and surfaces are refined before parts are painted in a clean, controlled environment. More inspections and further preparations are performed as caps and tonneaus are led to sophisticated paint spray booths where lighting, air pressure, humidity, temperature and filtration provide an ideal painting environment. Using automotive quality paints and OEM-matching paint formulas, highly trained painters apply a basecoat of color, then a clearcoat for UV protection and gloss. Each cap and tonneau is then sent through temperature-controlled heat tunnels to cure and set the fresh paint.

Window and door openings are carefully cut, headliners are added Caps are moved to the cutting operation, where openings for windows and doors are carefully marked, then precisely routed, so they can accept any of LEER's wide range of windows and doors. Our commercial grade marine carpet headliner option is installed at this point, too.

Hardware is added caps are water tested

Windows, doors, locks, latches, hinges, seals, and a wide range of other hardware and accessory options are added at this stage. Critical, built-in reinforcements of metal and wood are applied and the famous LEER logo is applied. All caps are water-tested, using either a water shower booth or ultrasonic leak detection equipment.

All products pass a final approval

Once the assembly process is complete, each and every unit leaving our plant undergoes a final inspection. Shipment is scheduled only after each cap and tonneau has passed that inspection. The result of the LEER manufacturing process is a truck cap or tonneau that is everything you want it to be: light, strong, resilient, precise and beautiful!

LEER Transportation

The bridge between LEER and your local LEER Dealer LEER operates its own fleet of tractor trucks towing custom-designed trailers, coast to coast, delivering LEER truck caps and tonneaus to the industry's largest network of dealers. The LEER fleet includes a wide range of delivery equipment to accommodate the unique dimensions and shipping considerations of our product line.

Dealer Prep

LEER Dealers often clean products that show road dust, etc. from their long journey from the plant. They remove the shipping boards and prepare your truck cap or tonneau for installation.


Your LEER Dealer carefully prepares your truck for installation, using highly specialized clamps to secure your new truck cap or tonneau to your truck. The Dealer makes critical adjustments to hinges, locks, latches and other mechanical features that require tight tolerances. Required electrical connections for the third brake light and other 12V features are made. After a final inspection and test of the operation of the features of your new LEER, it's yours to enjoy for years and years to come.