What Exactly Are Metal Shipping Containers Made Of?

Shipping Containers are effectively giant metal boxes with doors, so they're perfect as custom storage containers, but what are they made of?

Anatomy of a Shipping Container

Shipping Container Fans Say Metal Boxes Can Ease Housing, 49% OFF

Metal intermodal container - 20' - Bullbox - wood / storage / transport

Shipping Containers – a design primer

Intermodal container - Wikipedia

Stadium built with shipping containers reaches completion in Qatar

Aluminum Roll-Up Doors for Shipping Containers – Eagle Leasing

Conex Box vs. Storage Container vs. Shipping Container?

Extra-Wide Storage Containers

What are shipping containers made of? - Twisted S Explains