Find Your Flatbed Truck Tool Box Here

Outfitting your flatbed truck with the right tool box is one of the smartest investments you can make to protect your tools, stay organized, and get the job done right. Flatbeds offer versatility and open space, but without secure storage, your tools and equipment are left exposed to the elements and are at risk of damage or theft. That’s where a well-designed UWS tool box comes in.

Built for hardworking trucks and tough conditions, UWS tool boxes combine heavy-duty construction with smart storage solutions to help you haul with confidence. Whether you need a single side-mount box for easy access, a set of underbody boxes to maximize open deck space, or a custom setup for specialized gear, UWS has everything you need to outfit your flatbed truck to get the job done right.

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Underbody Tool Boxes for Flatbed Trucks

When you need secure storage that won’t take up valuable deck space, underbody tool boxes are the perfect solution. Mounted beneath the bed of your flatbed truck, UWS underbody boxes provide convenient, out-of-the-way storage for tools, equipment, and jobsite essentials — all while keeping your truck bed wide open for larger cargo.

Built to perform in tough conditions, UWS underbody boxes are constructed from extra-thick aluminum for superior strength without added weight. Each box features our signature RigidCore™ lid, filled with solid foam for enhanced structural integrity and reduced binding, plus stainless steel latches and hardware for long-lasting corrosion resistance. The underbody line is designed for easy access and dependable protection, helping you stay organized and work efficiently, no matter where the road takes you.

UWS Underbody Tool Box Key Features:

1. 0.075" Extra-Thick Aluminum Construction

UWS underbody tool boxes are built tough with extra-thick aluminum. That added thickness isn’t just for show. It means greater durability, stronger dent resistance, and a longer life no matter where the road takes you.

2. Stainless Steel T-Handle

UWS underbody tool boxes come equipped with rugged stainless steel T-handles, designed for dependable security and everyday ease of use. These corrosion-resistant latches offer a secure, weather-resistant seal while providing a comfortable grip even with gloves on

3. Stainless Steel Cables

Every UWS tool box is assembled with stainless steel cable supports that allow the door to open 90° for easy loading and unloading of tools and equipment.

Utility Chests for Flatbed Trucks

Utility chests are a versatile, all-purpose storage solution designed to sit securely on your flatbed, providing easy access to tools and equipment while keeping your gear protected from the elements. Unlike side-mounted or underbody boxes, utility chests are designed to offer maximum interior space and straightforward installation, making them a great fit for flatbeds that need flexible, reliable storage without sacrificing deck room.

UWS utility chests are built to handle the demands of hard work and harsh environments. Each chest features extra-thick aluminum construction for superior strength and durability, along with the UWS RigidCore™ foam-filled lid for enhanced structural integrity and smooth operation. With corrosion-resistant stainless steel latches, a self-opening lid with gas struts for convenient one-handed access, and a weather-resistant seal to keep moisture and dust out, UWS utility chests are made to secure your gear and keep your flatbed organized — so you're always ready for the next job.

UWS Utility Chest Key Features:

1. RigidCore Lid

RigidCore™ is a patented UWS innovation designed to reinforce the lid of every tool box. The lid is injected with a hardening, expanding foam, securely sealed between two layers of aluminum. Once cured, this creates a solid, unified structure that delivers exceptional strength and rigidity — far superior to conventional, hollow-lid designs.

2. Extra-thick Aluminum Construction

UWS tool boxes and storage chests are built to outlast and outperform, thanks to extra-thick aluminum construction. While many competitors rely on aluminum as thin as 0.045” to 0.050”, we use heavy-duty 0.058” diamond-plate aluminum for added durability and dependability.

3. Stainless Steel Paddle Handle

UWS utility chest boxes feature stainless steel paddle handles that combine sleek design with rugged functionality. These corrosion-resistant latches are built for smooth operation, offering a secure closure that keeps your gear protected from the elements.

Transfer Tanks for Flatbed Trucks

When the job demands extra fuel or liquid transport, transfer tanks are the solution you can count on. Designed to safely carry diesel fuel or other non-flammable liquids, transfer tanks for flatbed trucks let you refuel equipment and vehicles on-site, saving you time and keeping your operation moving without the need for frequent trips to the pump.

UWS transfer tanks are built for durability and peace of mind. Constructed from heavy-gauge aluminum, each tank is engineered to withstand the rigors of tough job sites and harsh environments, while remaining corrosion-resistant and lightweight. The tanks feature internal baffles to reduce sloshing and maintain stability during transport, along with a lockable, vented cap for safe and easy filling. UWS transfer tanks are designed for compatibility with a wide range of flatbed trucks and can be paired with UWS tool boxes for a complete, space-saving storage and fueling solution. Whether you're managing a farm, a construction crew, or a fleet of work trucks, UWS transfer tanks help you stay fueled, efficient, and ready for the next task.

UWS Transfer Tank Key Features:

1. Internal Baffles

UWS transfer tanks are engineered with internal baffles that help maintain stability during transport. These built-in reinforcements reduce fuel slosh and minimize shifting weight, especially during braking or cornering. The result is a safer, smoother ride and greater control even when the tank is full.

2. Commercial-grade Vented Cap

UWS transfer tanks are equipped with a commercial-grade vented cap featuring a reinforced collar for added strength and reliability. The vented design ensures proper airflow during fuel transfer, preventing pressure buildup and allowing for a smooth, consistent flow.

3. Drain Plug

UWS transfer tanks feature a convenient drain plug that makes maintenance fast and hassle-free. Whether you need to clean out old fuel, switch fluids, or perform routine upkeep, the drain plug allows for easy, controlled draining without the mess.

How to Choose the Right Tool Box for Your Flatbed Truck

Choosing the right storage setup for your flatbed truck isn’t just about picking a box — it’s about making sure your tools, equipment, and workflow stay efficient, secure, and ready for the road. Here are a few key considerations to help you select the best UWS tool box combination for your flatbed:

1. What Will You Be Using Your Truck For?
Your work dictates your storage needs. Are you hauling construction tools, farm equipment, maintenance gear, or a mix of everything? Knowing the type of equipment you carry helps determine whether you need quick-access side boxes, large-capacity utility chests, transfer tanks, or a custom combination of all three.

2. Do You Have Other Accessories Installed?
Before selecting your boxes, take stock of any existing equipment on your flatbed — like a gooseneck hitch, headache rack, mounted cranes, or specialized machinery. These accessories can affect where and how tool boxes can be mounted, so plan your layout for both accessibility and compatibility.

3. Do You Need One Box or Multiple?
One well-placed box might be enough for light-duty use, but if you carry a wide range of tools or travel long distances between job sites, multiple boxes can help you stay organized. Consider mixing underbody boxes, utility chests, and side boxes to make the most of your flatbed’s available space.

4. Know Your Bed Dimensions
Not all flatbeds are created equal. Always measure your truck bed — length, width, and mounting clearance — to ensure the tool boxes you select fit properly and allow for safe, secure installation.

5. Consider Accessibility
Think about how and where you’ll need to access your gear. Underbody boxes are great for out-of-the-way storage, while utility chests offer quick access from the bed. Side-mounted boxes and transfer tanks add even more specialized convenience depending on your needs.

6. Security & Weather Protection
Your tools are an investment — and so is the box you store them in. UWS tool boxes are built to stand up to the elements and deter theft, with features like stainless steel lock handles, RigidCore™ reinforced lids, and weather-resistant seals designed for real-world job site conditions.

7. Think Long-Term
A well-planned tool box setup not only makes your current job easier but also gives you flexibility as your needs evolve. Consider adding boxes that can grow with you — or leave room for expansion — so you’re not boxed in as your projects and equipment change.

Why Should You Choose a UWS Tool Box for Your Flatbed Truck?

Professional-Grade

UWS truck tool boxes are designed to meet the demands of hardworking professionals, offering durability, security and convenience.

Trusted Brand

We are a trusted name in the truck accessories industry, known for our commitment to quality and innovation.

Peace of Mind

With robust construction and reliable security features, you can trust UWS to keep your tools safe and secure, no matter where your work takes you.

Underbody Steel Boxes for Flatbed Trucks

Mounted beneath the truck bed or flatbed, UWS underbody steel boxes offer secure, out-of-the-way storage that’s ready for anything. They're ideal for service trucks, flatbeds, trailers, and other commercial setups where space is critical and protection is non-negotiable.

Built from high-strength steel and finished with a durable black powder coat, these boxes are engineered to withstand the harshest jobsite conditions — from road spray and flying gravel to long hauls through rough terrain. Their low-profile placement keeps tools and gear safely stowed without interfering with your bed space, making them perfect for operations that demand maximum cargo capacity up top.

UWS Underbody Steel Tool Box Key Features:

1. Heavy-Duty Steel Construction

UWS underbody steel tool boxes are built from extra-thick 14-gauge steel, which is tough enough to handle heavy tools, rough roads, and daily wear. The durable matte black powder coat finish adds another layer of protection, guarding against rust, chips, and scratches.

2. Stainless Steel T-Handle

UWS underbody tool boxes feature tough stainless steel T-handles built for daily reliability and long-lasting security. They’re corrosion-resistant to stand up to the elements and designed for a secure seal to keep out water and dirt.

3. Versatile Mounting Options

UWS steel underbody boxes are designed to mount above or below flatbeds trucks. With the 18” mounting brackets (sold separately), you can seamlessly integrate secure storage into your setup.

Transfer Tank Combos for Flatbed Trucks

If your truck is your mobile workspace, UWS combo transfer tanks make it more efficient than ever. These dual-function tanks combine a liquid transfer system with a secure storage box — saving space and streamlining your workflow.

Designed for hardworking professionals who need both portable fuel and reliable tool storage, UWS combo transfer tanks offer the best of both worlds in a single, compact solution. Whether you're fueling equipment in the field, running a farm operation, or managing a remote jobsite, these combo units help you get more done without hauling extra gear.

UWS Combo Transfer Tank Key Features:

1. Dual-Purpose Design

UWS combo transfer tanks transform your pickup truck by combining a liquid transfer tank, designed for diesel or other non-flammable fluids, with a spacious, integrated tool box for extra storage.

2. Internal Baffles

UWS transfer tanks are designed with internal baffles to enhance stability during transport. These innovative reinforcements help reduce fuel slosh and minimize shifting weight, especially when braking or cornering. The outcome is a safer, smoother driving experience with improved control, even when the tank is full.

commercial grade vented cap uws combo transfer tank

3. Commercial-grade Vented Cap

UWS transfer tanks feature a commercial-grade vented cap with a reinforced collar, providing superior strength and durability. The vented design ensures optimal airflow during fuel transfer, preventing pressure buildup and ensuring a smooth, consistent flow of fuel.

What Sets UWS Flatbed Tool Boxes Apart From the Rest

1. RigidCore Lid

RigidCore™ is a patented UWS innovation that adds serious backbone to every tool box lid. Instead of a hollow design, we inject expanding foam between two layers of aluminum, creating a solid, unified lid structure. Once cured, it dramatically boosts strength, resists warping, and holds up to the daily grind far better than traditional designs.

Microseal Gasket for flatbed truck tool box

2. MicroSeal Gasket

The MicroSeal™ gasket is your first line of defense against the elements. It forms a tight, consistent seal around the lid, locking out water, dust, and debris so your tools stay protected, clean, and ready to work as hard as you do.

3. Assembled in the USA

All UWS tool boxes are proudly assembled in Perry, Florida. We believe in American manufacturing because it means higher standards, better craftsmanship, and a product you can trust day in and day out.

Flatbed Truck Tool Box FAQs

1. What type of tool box is best for a flatbed truck?

The best tool box depends on your needs and setup. Underbody boxes are ideal for saving deck space, utility chests offer large-capacity storage on the bed, and side-mounted boxes provide easy access. Many flatbed owners use a combination of box types for a complete storage solution.

2. Will a standard truck tool box fit on a flatbed?

Not always. Flatbed trucks have different mounting surfaces and clearances compared to traditional pickup beds. It's important to measure your flatbed and choose tool boxes specifically designed or suited for flatbed applications.

3. How do you mount a tool box to a flatbed truck?

Tool boxes for flatbeds are typically bolted directly to the bed frame or mounting brackets. Underbody boxes are mounted beneath the bed using welded or bolt-on brackets, while utility chests and side boxes are mounted to the deck surface. Always follow manufacturer guidelines and use corrosion-resistant hardware.

4. Can I use a UWS transfer tank with a tool box on my flatbed?

Yes! UWS offers combo models that pair transfer tanks with matching tool boxes, saving space and providing both storage and fuel capacity in one compact unit. These are ideal for jobs that require frequent refueling of equipment in the field.

5. Are UWS tool boxes weather resistant?

Yes — UWS tool boxes are built with a MicroSeal™ gasket to keep out moisture, dust, and debris. The design ensures your tools stay dry and protected in rain, snow, or rugged jobsite conditions.

6. Where can I buy UWS tool boxes for my flatbed?

UWS tool boxes are available at authorized dealers nationwide, as well as through leading online retailers.

Disclaimers: These photographs, recommendations, and approximations are intended for demonstration purposes only and do not reflect the specifications of any particular tow vehicle, recreational vehicle, or trailer. Always consult the manufacturer’s Owner's Manual. All third-party product names, logos, brands, and other trademarks shown are the property of their respective trademark holders, and use of them does not imply any affiliation with or endorsement by them.