Everything You Need to Know About Conex Boxes

Whether you’ve decided to buy Conex boxes for your belongings or need to know more before you consider a Conex box for sale or to rent, Eagle Leasing is your best source. 

Today, it’s easy to spot a Conex storage box. People use them frequently for moving to a new home or renovating businesses — or, in some cases, converting them into homes or businesses. These Conex storage boxes have something in common with Jeep SUVs, Silly Putty, weather radar, and even duct tape: their first use occurred with the U.S. military. Today, they are more commonly known as shipping containers or storage containers, but back in the days of World War II, they were known as “transporters.”

The Need for Safe Transport

Throughout the war, the U.S. Army was hamstrung with cargo delays based on the time it took to load and unload ships. The Army faced another problem that small business owners and retailers are well acquainted with: loss prevention. Because that cargo was loose, it was subject to getting damaged or swiped — and that led to the Army losing money.

According to the U.S. Army Transportation Museum, the Army in ‘48 started experimenting with some pilot models of reusable steel containers that were capable of carrying about 9,000 pounds. At about 8-by-6-by-6 feet, the original Conex box dimensions allowed for a design with double doors on one end elevated skids on the bottom, and lifting rings on the top.

Successful Tests

The prototypes were successful enough for an expanded test in ‘51, where an additional 100 transporters were commissioned for use by the Far East Command in the Korean War. Used primarily to ship items from Japan to Korea, making their final trips on railroad cars directly to supply points, they were tested and evaluated for how well they carried valuable, critical, or sensitive items.

The program was successful enough to expand. In ‘52, some tweaks were made, including a name change to Container Express (the origin of the term “Conex box”). This time, engineering supplies and spare parts were shipped from Columbus General Depot in Georgia to the Port of San Francisco, where the containers were loaded on ships bound for Japan and Korea. Army officials found the new boxes reduced transportation time, knocking more than 20 days off a shipment that normally took about 55 days. 

shipping-containers Everything You Need to Know About Conex Boxes


Conex boxes became critical for logistics support in the ensuing Vietnam War. As ubiquitous as Huey helicopters and aces of spades, Conex boxes delivered spare parts, supplies, and more to U.S. troops stationed across the region during that war.

Demonstrating their second life as a usable structure, many of those Conex boxes never made it back to the U.S. They were repurposed into command posts, bunkers, dispensaries, and more. 

It didn’t take long for the private sector to take notice. Commercial industries started developing their own versions of Conex boxes, and Sea-Land Container Services designed special ships intended to carry only storage containers.

Conex Storage Container Rental

At Eagle Leasing, we are grateful for the generations of veterans who have defended our freedom across the globe and thankful for how the military’s innovations have benefitted citizens. Our business also stretches across generations — since our origins in 1967, we saw how the use of Conex boxes grew. We are proud to offer Conex storage container rental and lease services to customers in need of shipping containers. 

Contact us today to find out how product quality and customer satisfaction has helped us grow into the Northeast’s largest container and trailer leasing company.