Drop Down Door Underbody Box

No road's too rough for these military-grade boxes.

The HPI Drop Down Door Underbody Boxes are equipped with spring-loaded locking rods to prevent the everyday road vibrations from rattlling doors open on the highway and allowing expensive tie-down equipment or tools to fall out. In fact, the more vibration you get, the more they try to close. A divider option placed on one side of the underbody tool box keeps tie-down chains from drifting around the tool box.

What else? Nothing is more frustrating than opening your tool box and seeing your tools in a puddle of water. That's why we use Clean Seal™ automotive stripping around the edges of each toolbox to ensure a watertight seal. The stripping is made of closed-cell rubber with a hollow core. This allows the rubber to conform to curves, corners and varying cross sections without bridging or creasing.

Like our Drop Down Door Underbody Box but want something special done to it? Call our sales team now to start creating your own custom variant!

HPI Benefits

The HPI difference is in the materials we use, the attention to all details and ultimately products we produce and proudly guarantee. Our promise is to take the best care of your product while we manufacture it, and continue to care for a lifetime after you receive it.

Lifetime Warranty

All of our products come with a Lifetime Warranty against defects in manufacturing (failed welds, etc.). It also includes all locking mechanisms, hinges, gas shocks, weatherstripping and any other materials we use. Learn More

Military Grade Aluminum

Highway Products uses nothing but the best materials. Our products are hand crafted out of Military Grade aluminum. Why take it that far? The days of using nothing but the best ingredients are all but gone in this world. We refuse to sink to that level. That’s the HPI difference.

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Hand-Made in the USA

Hand crafted from beginning to end right here in the USA. Every square inch of our products are touched by human hands, every step of the way.

This product can expose you to chemicals that are known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.

Product Features

All HPI products come standard with options and features that you would normally pay extra for. Please explore all of our standard and optional features and call us with any questions you may have!

  • 5052 Smooth Aluminum
    We build our Drop Down Door Underbody Box from rust-free 5052 aluminum, the same material used by the military, aircraft manufactures and boat builders.
  • T Handle Locks
    Our ergonomically designed T-Handle locks are the most secure locking mechanism on the market.
  • Watertight Seal
    We use Clean Seal™ automotive stripping around the edges of each toolbox to ensure a watertight seal.
  • Piano Hinges
    Piano hinges provide full-length support and reduces stress points caused by inferior hinges.
  • Reinforced Strength
    Highway Products tool boxes are reinforced and reinforced again. That's why they last for millions of miles. We didn't get our reputation from skimping. Our underbody boxes are built with Herculean strength.
  • Stainless Steel Torx Screws
    Stainless steel Torx screws are the toughest fasteners on the market today. These fasteners won't loosen as you drive down the road and a door can be replaced without a special rivet gun.
  • Angle Bracing
    One of the weak points of truck tool boxes is the bottom corners. There is so much road stress from carrying heavy tarps, chains, tools, and other equipment, the corners sometimes break. Highway Products has eliminated this problem with reinforced angle bracing welded in the corners.
  • Pull Out Drawers
    Great organizational tool - we can make them in any size and we have different weight capacities to meet your needs.
  • Optional Dividers
    A divider option placed on one side of the underbody tool box keeps tie-down chains from drifting around the tool box, plus a hanging bar.

Drop Down Door Underbody Box Videos

Drop Down Door Underbody Box Images


Smooth Aluminum

Popular on semi truck boxes, ranch set ups and accents. This is the ultimate, no maintenance, classic look.

Diamond Plate

Diamond Plate

Tried and true. The all time classic finish. Rugged, durable and will last forever.

Interested in our Drop Down Door Underbody Box?

Our team of Product Specialists are on standby to answer any remaining questions you have about our Drop Down Door Underbody Box or to assist you in placing your order.

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