Most commonly used for mounting processors, audio amplifiers, power/signal distributors and etc, this case has rack strip mounted at front and (or) rear.
Rack case comes in flotation/non-flotation types. Flotation case is designed for better protection of equipment by building another case inside eixsting case and put 30mm EVA in between for shockproof purpose.
The front and rear lid can come with fold-able desk stand/legs built in, so they can be setup as extra desktop next to the road case when needed. This type of case is also called workstations.