LEER 100XL Truck Topper – Premium Fiberglass Cap

★★★★★4.8/5· thousands of reviews

The LEER 100XL is our flagship mid-profile fiberglass topper, engineered for drivers who demand both style and substance. Its flush-mount design sits lower than traditional high-rise caps, reducing wind drag and improving fuel economy without sacrificing interior headroom. We built this topper with a one-piece fiberglass shell reinforced at stress points, so it won’t warp or fade after years of highway miles and sun exposure.

Whether you’re hauling gear to the jobsite or loading up for a weekend camping trip, the 100XL keeps everything secure and dry. Factory-matched paint and tinted windows give your truck a factory-installed look, while our continuous weather seal system blocks rain, snow, and road dust at every seam. This is the LEER topper that works as hard as you do.

  • One-piece fiberglass construction with UV-resistant gelcoat finish
  • Mid-profile height (approx. 30–32 inches) for improved aerodynamics
  • Continuous bulb seal weather stripping on all door openings
  • Tinted safety-glass side windows and rear barn doors
  • Factory paint-match service available for OEM color coordination
One-piece fiberglass construction with UV-resistant gelcoat finishMid-profile height (approx. 30–32 inches) for improved aerodynamicsContinuous bulb seal weather stripping on all door openingsTinted safety-glass side windows and rear barn doorsFactory paint-match service available for OEM color coordination
Build quality
Everyday use
Value
Durability
Style

Fiberglass Shell Construction & Finish

Fiberglass Shell Construction & Finish

We mold every 100XL shell in a single piece to eliminate the flex and rattles common in multi-panel designs. The fiberglass layup uses continuous-strand mat and woven roving for tensile strength, then cures with a UV-stable gelcoat that resists chalking and oxidation. Unlike aluminum or ABS plastic caps, fiberglass won’t dent from hail or crack in sub-zero temperatures.

Factory paint matching is handled through our in-house process—send us your truck’s paint code and we’ll spray the topper before delivery. The finish integrates a two-stage urethane clear coat for scratch resistance and long-term gloss retention. Minor scuffs can be buffed out with standard automotive compound, and the gelcoat layer underneath provides built-in color depth that won’t flake or peel.


Aerodynamic Profile & Fuel Efficiency

Aerodynamic Profile & Fuel Efficiency

The 100XL’s mid-height roofline tapers from front to rear, directing airflow over the tailgate instead of creating the parachute effect you get with tall, boxy caps. Independent testing shows that a well-fitted mid-profile topper like the 100XL can reduce highway drag by 12–18 percent compared to driving with an open bed, translating to measurable fuel savings on long hauls.

Our front-slope angle matches the cab rake on most modern trucks, so there’s no abrupt air-barrier at the topper’s leading edge. Roof supports are recessed into the shell to minimize turbulence, and the rear barn doors close flush with the body to prevent air pockets. If you tow a trailer regularly, this streamlined design also reduces the buffeting and crosswind push that taller caps introduce.


Weather Seal System & Water Protection

Weather Seal System & Water Protection

Every door opening on the 100XL—barn doors, side lift gates, and optional sliding front window—uses a continuous bulb seal made from EPDM rubber. The seal compresses against an aluminum extrusion frame when the door latches, creating a watertight gasket that holds up through car washes and heavy rain. We also run a perimeter bulb seal where the topper meets the truck bed rail, and that seal sits inside a recessed channel to prevent wind lift at highway speeds.

Installation clamps pull the topper down evenly onto the bed rail, so there’s no gap for water to wick through. The rear barn doors latch at three points—top, middle, and bottom—to maintain even pressure across the seal. After five years of use, the EPDM rubber retains its compression set better than foam or vinyl alternatives, so you won’t need to replace gaskets as often.


More LEER Toppers for Every Work & Adventure Style

LEER 100XQ Truck Topper
LEER 100XQ Truck Topper
Mid-profile cap with frameless side glass for a sleeker sightline and larger windows
View the 100XQ →
LEER 180 Truck Topper
LEER 180 Truck Topper
High-rise fiberglass cap offering maximum interior headroom and walk-in rear access
Explore the 180 →
LEER 122 Work Cap
LEER 122 Work Cap
Commercial-grade aluminum topper with ladder racks and tool-box integration
See the 122 →
LEER Sport Tonneau Cover
LEER Sport Tonneau Cover
Low-profile hard folding cover for bed protection with quick bed access
Check Sport Cover →
LEER DCC Commercial Cap
LEER DCC Commercial Cap
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View DCC Series →
LEER Locker Truck Box
LEER Locker Truck Box
Lockable aluminum toolbox designed to mount inside LEER toppers for secure gear storage
Shop Locker Box →

What people are saying

4.8
★★★★★
Based on verified reviews
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M
Mike T.
Verified buyer
★★★★★
Perfect fit and finish on my F-150
I ordered the factory paint match and it’s impossible to tell the topper wasn’t installed at the dealership. The barn doors seal tight even after a week of rain, and the headliner makes the bed feel like an extension of the cab. Installation took about 45 minutes with two people.
C
Carlos R.
Verified buyer
★★★★★
Noticeable fuel savings on highway trips
I drive about 400 miles a week for work, and my fuel economy improved by almost 2 MPG after installing the 100XL. The aerodynamic profile really does make a difference compared to my old boxy cap. Wind noise is also way down.
J
Jennifer K.
Verified buyer
★★★★★
Keeps tools dry and secure
I’ve had this topper for three years now and haven’t had a single leak. The rubber seals still compress like new, and the locking barn doors give me peace of mind when I leave expensive tools in the bed overnight.
B
Brian L.
Verified buyer
★★★★☆
Great topper, could use brighter interior light
The build quality is excellent and the paint match was spot-on. My only complaint is the optional LED dome light isn’t very bright—I ended up adding a battery-powered strip light along the side. Otherwise, this is a solid investment.
D
David M.
Verified buyer
★★★★★
Best cap I’ve owned in 20 years
I’ve gone through four different truck caps over two decades, and the 100XL is the first one that hasn’t warped or faded after two years. The fiberglass holds up way better than the ABS plastic caps I used to buy.
A
Amanda S.
Verified buyer
★★★★★
Looks factory-installed, works flawlessly
We use this topper on our work trucks and it’s been bulletproof. The roof rack mounts hold our ladder system without flex, and the rear doors still close smoothly after 50,000 miles of use. Highly recommend for fleet buyers.

Common Questions About the LEER 100XL

The 100XL is manufactured in configurations for Ford F-Series, Chevy Silverado, GMC Sierra, Ram 1500–3500, Toyota Tundra and Tacoma, and Nissan Titan and Frontier. We produce versions for 5.5-foot, 6.5-foot, and 8-foot bed lengths. During ordering, provide your truck’s year, make, model, and bed length—our team will confirm fitment and select the correct mounting hardware. If you have an aftermarket bed liner or tonneau rail system, mention that as well so we can adjust clamp heights.

Paint-matching adds approximately 7–10 business days to the standard build time. You’ll need to provide your truck’s manufacturer paint code, which is usually found on a sticker inside the driver’s door jamb. We spray the topper with a two-stage urethane system that matches OEM color and gloss level. Once cured, the finish is ready for installation with no additional prep work required.

Yes, the 100XL roof is reinforced to support aftermarket crossbars and rack systems. The fiberglass shell includes recessed mounting channels that accept most clamp-on rack bases without drilling. Static load capacity is 300 pounds evenly distributed; dynamic load during driving should not exceed 150 pounds. Popular compatible systems include Thule, Yakima, and Rhino-Rack crossbars.

The 100XL uses traditional framed side windows with visible aluminum trim, while the 100XQ features frameless flush-mount glass for a sleeker appearance and larger window area. Both models share the same one-piece fiberglass shell, mid-profile height, and weather seal system. The 100XQ typically costs 10–15 percent more due to the frameless glass upgrade.

Clean the EPDM rubber seals every few months with mild soap and water to remove dirt and road grime. After cleaning, apply a silicone-based protectant spray to keep the rubber supple and prevent cracking. Avoid petroleum-based products, which can degrade EPDM. If a seal becomes compressed or damaged, replacement bulb seal is available through our parts department and installs in the existing aluminum channels without tools.

We back the 100XL with a three-year limited warranty covering defects in materials and workmanship. The fiberglass shell, door frames, hinges, and latches are all covered. Normal wear items like weather seals and paint finish are covered for the first year. If you experience any issues during the warranty period, contact our service team for repair or replacement authorization.

Yes, the front sliding window option can be retrofitted by a LEER-authorized installer. The fiberglass shell is pre-molded with a reinforced opening at the front, so installation involves cutting the gelcoat, inserting the slider frame, and sealing the perimeter. Most installers complete the upgrade in 2–3 hours. Contact us for a list of certified shops in your area.

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