What is a CONEX anyway?

Answer? A used shipping container

Steel Shipping Containers are large, durable, tractor-trailer sized boxes used to ship items, generally from overseas originating points to this country.  An after-market for these 20' and 40' containers has evolved over the years for these very useful, durable steel containers.
The steel storage container is also known as intermodal container, freight container, iso container, shipping container, hi-cube container, conex box, conex container, and sea can. 
These containers can be converted with framing build-out, air-conditioning, refrigeration, electrical wiring, or whatever is required to provide the desired solution.